Authors/Thomas Aquinas/Summa Theologiae/Part IIb/Q70

• Question 70.1 Or by the witnesses
• Question 70.2
• Question 70.3
• Question 70.4

Latin	English
IIª-IIae q. 70 pr. Deinde considerandum est de iniustitia pertinente ad personam testis. Et circa hoc quaeruntur quatuor. Primo, utrum homo teneatur ad testimonium ferendum. Secundo, utrum duorum vel trium testimonium sufficiat. Tertio, utrum alicuius testimonium repellatur absque eius culpa. Quarto, utrum perhibere falsum testimonium sit peccatum mortale.	Question 70. Injustice with regard to the person of the witness 1. Is a man bound to give evidence? 2. Does the evidence of two or three witnesses suffice? 3. May a man's evidence be rejected without any fault on his part? 4. Is it a mortal sin to bear false witness?
IIª-IIae q. 70 a. 1 arg. 1 Ad primum sic proceditur. Videtur quod homo non teneatur ad testimonium ferendum. Dicit enim Augustinus, in quaest. Gen., quod Abraham dicens de uxore sua, soror mea est, veritatem celari voluit, non mendacium dici. Sed veritatem celando aliquis a testificando abstinet. Ergo non tenetur aliquis ad testificandum.	Objection 1. It would seem that a man is not bound to give evidence. Augustine say (QQ. Genesis 1:26) [Cf. Contra Faust. xxii, 33,34, that when Abraham said of his wife (Genesis 20:2), "She is my sister," he wished the truth to be concealed and not a lie be told. Now, by hiding the truth a man abstains from giving evidence. Therefore a man is not bound to give evidence.
IIª-IIae q. 70 a. 1 arg. 2 Praeterea, nullus tenetur fraudulenter agere. Sed Prov. XI dicitur, qui ambulat fraudulenter revelat arcana, qui autem fidelis est celat amici commissum. Ergo non tenetur homo semper ad testificandum, praesertim super his quae sunt sibi in secreto ab amico commissa.	Objection 2. Further, no man is bound to act deceitfully. Now it is written (Proverbs 11:13): "He that walketh deceitfully revealeth secrets, but he that is faithful concealeth the thing committed to him by his friend." Therefore a man is not always bound to give evidence, especially on matters committed to him as a secret by a friend.
IIª-IIae q. 70 a. 1 arg. 3 Praeterea, ad ea quae sunt de necessitate salutis maxime tenentur clerici et sacerdotes. Sed clericis et sacerdotibus prohibetur ferre testimonium in causa sanguinis. Ergo testificari non est de necessitate salutis.	Objection 3. Further, clerics and priests, more than others, are bound to those things that are necessary for salvation. Yet clerics and priests are forbidden to give evidence when a man is on trial for his life. Therefore it is not necessary for salvation to give evidence.
IIª-IIae q. 70 a. 1 s. c. Sed contra est quod Augustinus dicit, qui veritatem occultat, et qui prodit mendacium, uterque reus est, ille quia prodesse non vult, iste quia nocere desiderat.	On the contrary, Augustine [Can. Quisquis, caus. xi, qu. 3, cap. Falsidicus; cf. Isidore, Sentent. iii, 55 says: "Both he who conceals the truth and he who tells a lie are guilty, the former because he is unwilling to do good, the latter because he desires to hurt."
IIª-IIae q. 70 a. 1 co. Respondeo dicendum quod in testimonio ferendo distinguendum est. Quia aliquando requiritur testimonium alicuius, aliquando non requiritur. Si requiritur testimonium alicuius subditi auctoritate superioris cui in his quae ad iustitiam pertinent obedire tenetur, non est dubium quin teneatur testimonium ferre in his in quibus secundum ordinem iuris testimonium ab eo exigitur, puta in manifestis, et in his de quibus infamia praecessit. Si autem exigatur ab eo testimonium in aliis, puta in occultis et de quibus infamia non praecessit, non tenetur ad testificandum. Si vero requiratur eius testimonium non auctoritate superioris cui obedire tenetur, tunc distinguendum est. Quia si testimonium requiratur ad liberandum hominem vel ab iniusta morte seu poena quacumque, vel a falsa infamia, vel etiam ab iniquo damno, tunc tenetur homo ad testificandum. Et si eius testimonium non requiratur, tenetur facere quod in se est ut veritatem denuntiet alicui qui ad hoc possit prodesse. Dicitur enim in Psalm., eripite pauperem, et egenum de manu peccatoris liberate; et Prov. XXIV, erue eos qui dicuntur ad mortem. Et Rom. I dicitur, digni sunt morte non solum qui faciunt, sed etiam qui consentiunt facientibus, ubi dicit Glossa, consentire est tacere, cum possis redarguere. Super his vero quae pertinent ad condemnationem alicuius, non tenetur aliquis ferre testimonium nisi cum a superiori compellitur secundum ordinem iuris. Quia si circa hoc veritas occultetur, nulli ex hoc speciale damnum nascitur. Vel, si immineat periculum accusatori, non est curandum, quia ipse se in hoc periculum sponte ingessit. Alia autem ratio est de reo, cui periculum imminet eo nolente.	I answer that, We must make a distinction in the matter of giving evidence: because sometimes a certain man's evidence is necessary, and sometimes not. If the necessary evidence is that of a man subject to a superior whom, in matters pertaining to justice, he is bound to obey, without doubt he is bound to give evidence on those points which are required of him in accordance with the order of justice, for instance on manifest things or when ill-report has preceded. If however he is required to give evidence on other points, for instance secret matters, and those of which no ill-report has preceded, he is not bound to give evidence. On the other hand, if his evidence be required by authority of a superior whom he is bound to obey, we must make a distinction: because if his evidence is required in order to deliver a man from an unjust death or any other penalty, or from false defamation, or some loss, in such cases he is bound to give evidence. Even if his evidence is not demanded, he is bound to do what he can to declare the truth to someone who may profit thereby. For it is written (Psalm 81:4): "Rescue the poor, and deliver the needy from the hand of the sinner"; and (Proverbs 24:11): "Deliver them that are led to death"; and (Romans 1:32): "They are worthy of death, not only they that do them, but they also that consent to them that do them," on which words a gloss says: "To be silent when one can disprove is to consent." On matters pertaining to a man's condemnation, one is not bound to give evidence, except when one is constrained by a superior in accordance with the order of justice; since if the truth of such a matter be concealed, no particular injury is inflicted on anyone. Or, if some danger threatens the accuser, it matters not since he risked the danger of his own accord: whereas it is different with the accused, who incurs the danger against his will.
IIª-IIae q. 70 a. 1 ad 1 Ad primum ergo dicendum quod Augustinus loquitur de occultatione veritatis in casu illo quando aliquis non compellitur superioris auctoritate veritatem propalare; et quando occultatio veritatis nulli specialiter est damnosa.	Reply to Objection 1. Augustine is speaking of concealment of the truth in a case when a man is not compelled by his superior's authority to declare the truth, and when such concealment is not specially injurious to any person.
IIª-IIae q. 70 a. 1 ad 2 Ad secundum dicendum quod de illis quae homini sunt commissa in secreto per confessionem, nullo modo debet testimonium ferre, quia huiusmodi non scit ut homo, sed tanquam Dei minister, et maius est vinculum sacramenti quolibet hominis praecepto. Circa ea vero quae aliter homini sub secreto committuntur, distinguendum est. Quandoque enim sunt talia quae, statim cum ad notitiam hominis venerint, homo ea manifestare tenetur, puta si pertineret ad corruptionem multitudinis spiritualem vel corporalem, vel in grave damnum alicuius personae, vel si quid aliud est huiusmodi, quod quis propalare tenetur vel testificando vel denuntiando. Et contra hoc debitum obligari non potest per secreti commissum, quia in hoc frangeret fidem quam alteri debet. Quandoque vero sunt talia quae quis prodere non tenetur. Unde potest obligari ex hoc quod sibi sub secreto committuntur. Et tunc nullo modo tenetur ea prodere, etiam ex praecepto superioris, quia servare fidem est de iure naturali; nihil autem potest praecipi homini contra id quod est de iure naturali.	Reply to Objection 2. A man should by no means give evidence on matters secretly committed to him in confession, because he knows such things, not as man but as God's minister: and the sacrament is more binding than any human precept. But as regards matters committed to man in some other way under secrecy, we must make a distinction. Sometimes they are of such a nature that one is bound to make them known as soon as they come to our knowledge, for instance if they conduce to the spiritual or corporal corruption of the community, or to some grave personal injury, in short any like matter that a man is bound to make known either by giving evidence or by denouncing it. Against such a duty a man cannot be obliged to act on the plea that the matter is committed to him under secrecy, for he would break the faith he owes to another. On the other hand sometimes they are such as one is not bound to make known, so that one may be under obligation not to do so on account of their being committed to one under secrecy. On such a case one is by no means bound to make them known, even if the superior should command; because to keep faith is of natural right, and a man cannot be commanded to do what is contrary to natural right.
IIª-IIae q. 70 a. 1 ad 3 Ad tertium dicendum quod operari vel cooperari ad occisionem hominis non competit ministris altaris, ut supra dictum est. Et ideo secundum iuris ordinem compelli non possunt ad ferendum testimonium in causa sanguinis.	Reply to Objection 3. It is unbecoming for ministers of the altar to slay a man or to cooperate in his slaying, as stated above (Question 64, Article 4); hence according to the order of justice they cannot be compelled to give evidence when a man is on trial for his life.
IIª-IIae q. 70 a. 2 arg. 1 Ad secundum sic proceditur. Videtur quod non sufficiat duorum vel trium testimonium. Iudicium enim certitudinem requirit. Sed non habetur certitudo veritatis per dictum duorum testium, legitur enim III Reg. XXI quod Naboth ad dictum duorum testium falso condemnatus est. Ergo duorum vel trium testimonium non sufficit.	Objection 1. It would seem that the evidence of two or three persons is not sufficient. For judgment requires certitude. Now certitude of the truth is not obtained by the assertions of two or three witnesses, for we read that Naboth was unjustly condemned on the evidence of two witnesses (1 Kings 21). Therefore the evidence of two or three witnesses does not suffice.
IIª-IIae q. 70 a. 2 arg. 2 Praeterea, testimonium, ad hoc quod sit credibile, debet esse concors. Sed plerumque duorum vel trium testimonium in aliquo discordat. Ergo non est efficax ad veritatem in iudicio probandam.	Objection 2. Further, in order for evidence to be credible it must agree. But frequently the evidence of two or three disagrees in some point. Therefore it is of no use for proving the truth in court.
IIª-IIae q. 70 a. 2 arg. 3 Praeterea, II, qu. IV, dicitur, praesul non damnetur nisi in septuaginta duobus testibus. Presbyter autem cardinalis nisi quadraginta quatuor testibus non deponatur. Diaconus cardinalis urbis Romae nisi in viginti octo testibus non condemnabitur. Subdiaconus, acolythus, exorcista, lector, ostiarius, nisi in septem testibus non condemnabitur. Sed magis est periculosum peccatum eius qui in maiori dignitate constitutus est, et ita minus est tolerandum. Ergo nec in aliorum condemnatione sufficit duorum vel trium testimonium.	Objection 3. Further, it is laid down (Decret. II, qu. iv, can. Praesul.): "A bishop shall not be condemned save on the evidence of seventy-two witnesses; nor a cardinal priest of the Roman Church, unless there be sixty-four witnesses. Nor a cardinal deacon of the Roman Church, unless there be twenty-seven witnesses; nor a subdeacon, an acolyte, an exorcist, a reader or a doorkeeper without seven witnesses." Now the sin of one who is of higher dignity is more grievous, and consequently should be treated more severely. Therefore neither is the evidence of two or three witnesses sufficient for the condemnation of other persons.
IIª-IIae q. 70 a. 2 s. c. Sed contra est quod dicitur Deut. XVII, in ore duorum vel trium testium peribit qui interficietur; et infra, XIX, in ore duorum vel trium testium stabit omne verbum.	On the contrary, It is written (Deuteronomy 17:6): "By the mouth of two or three witnesses shall he die that is to be slain," and further on (Deuteronomy 19:15): "In the mouth of two or three witnesses every word shall stand."
IIª-IIae q. 70 a. 2 co. Respondeo dicendum quod, secundum philosophum, in I Ethic., certitudo non est similiter quaerenda in omni materia. In actibus enim humanis, super quibus constituuntur iudicia et exiguntur testimonia, non potest haberi certitudo demonstrativa, eo quod sunt circa contingentia et variabilia. Et ideo sufficit probabilis certitudo, quae ut in pluribus veritatem attingat, etsi in paucioribus a veritate deficiat. Est autem probabile quod magis veritatem contineat dictum multorum quam dictum unius. Et ideo, cum reus sit unus qui negat, sed multi testes asserunt idem cum actore, rationabiliter institutum est, iure divino et humano, quod dicto testium stetur. Omnis autem multitudo in tribus comprehenditur, scilicet principio, medio et fine, unde secundum philosophum, in I de coelo, omne et totum in tribus ponimus. Ternarius quidem constituitur asserentium, cum duo testes conveniunt cum actore. Et ideo requiritur binarius testium, vel, ad maiorem certitudinem, ut sit ternarius, qui est multitudo perfecta, in ipsis testibus. Unde et Eccle. IV dicitur, funiculus triplex difficile rumpitur. Augustinus autem, super illud Ioan. VIII, duorum hominum testimonium verum est, dicit quod in hoc est Trinitas secundum mysterium commendata, in qua est perpetua firmitas veritatis.	I answer that, According to the Philosopher (Ethic. i, 3), "we must not expect to find certitude equally in every matter." For in human acts, on which judgments are passed and evidence required, it is impossible to have demonstrative certitude, because they a about things contingent and variable. Hence the certitude of probability suffices, such as may reach the truth in the greater number, cases, although it fail in the minority. No it is probable that the assertion of sever witnesses contains the truth rather than the assertion of one: and since the accused is the only one who denies, while several witness affirm the same as the prosecutor, it is reasonably established both by Divine and by human law, that the assertion of several witnesses should be upheld. Now all multitude is comprised of three elements, the beginning, the middle and the end. Wherefore, according to the Philosopher (De Coelo i, 1), "we reckon 'all' and 'whole' to consist of three parts." Now we have a triple voucher when two agree with the prosecutor: hence two witnesses are required; or for the sake of greater certitude three, which is the perfect number. Wherefore it is written (Ecclesiastes 4:12): "A threefold cord is not easily broken": and Augustine, commenting on John 8:17, "The testimony of two men is true," says (Tract. xxxvi) that "there is here a mystery by which we are given to understand that Trinity wherein is perpetual stability of truth."
IIª-IIae q. 70 a. 2 ad 1 Ad primum ergo dicendum quod, quantacumque multitudo testium determinaretur, posset quandoque testimonium esse iniquum, cum scriptum sit Exod. XXIII, ne sequaris turbam ad faciendum malum. Nec tamen, quia non potest in talibus infallibilis certitudo haberi, debet negligi certitudo quae probabiliter haberi potest per duos vel tres testes, ut dictum est.	Reply to Objection 1. No matter how great a number of witnesses may be determined, the evidence might sometimes be unjust, since is written (Exodus 23:2): "Thou shalt not follow the multitude to do evil." And yet the fact that in so many it is not possible to have certitude without fear of error, is no reason why we should reject the certitude which can probably be had through two or three witnesses, as stated above.
IIª-IIae q. 70 a. 2 ad 2 Ad secundum dicendum quod discordia testium in aliquibus principalibus circumstantiis, quae variant substantiam facti, puta in tempore vel loco vel in personis de quibus principaliter agitur, aufert efficaciam testimonii, quia si discordant in talibus, videntur singulares esse in suis testimoniis, et de diversis factis loqui; puta si unus dicat hoc factum esse tali tempore vel loco, alius alio tempore vel loco, non videntur de eodem facto loqui. Non tamen praeiudicatur testimonio si unus dicat se non recordari, et alius asserat determinatum tempus vel locum. Et si in talibus omnino discordaverint testes actoris et rei, si sint aequales numero et pares dignitate, statur pro reo, quia facilior debet esse iudex ad absolvendum quam ad condemnandum; nisi forte in causis favorabilibus, sicut est causa libertatis et huiusmodi. Si vero testes eiusdem partis dissenserint, debet iudex ex motu sui animi percipere cui parti sit standum, vel ex numero testium, vel ex dignitate eorum, vel ex favorabilitate causae, vel ex conditione negotii et dictorum. Multo autem magis testimonium unius repellitur si sibi ipsi dissideat interrogatus de visu et scientia. Non autem si dissideat interrogatus de opinione et fama, quia potest secundum diversa visa et audita diversimode motus esse ad respondendum. Si vero sit discordia testimonii in aliquibus circumstantiis non pertinentibus ad substantiam facti, puta si tempus fuerit nubilosum vel serenum, vel si domus fuerit picta aut non, aut aliquid huiusmodi, talis discordia non praeiudicat testimonio, quia homines non consueverunt circa talia multum sollicitari, unde facile a memoria elabuntur. Quinimmo aliqua discordia in talibus facit testimonium credibilius, ut Chrysostomus dicit, super Matth., quia si in omnibus concordarent, etiam in minimis, viderentur ex condicto eundem sermonem proferre. Quod tamen prudentiae iudicis relinquitur discernendum.	Reply to Objection 2. If the witnesses disagree certain principal circumstances which change the substance of the fact, for instance in time, place, or persons, which are chiefly in question, their evidence is of no weight, because if they disagree in such things, each one would seem to be giving distinct evidence and to be speaking of different facts. For instance, one say that a certain thing happened at such and such a time or place, while another says it happened at another time or place, they seem not to be speaking of the same event. The evidence is not weakened if one witness says that he does not remember, while the other attests to a determinate time or place And if on such points as these the witness for prosecution and defense disagree altogether, and if they be equal in number on either side, and of equal standing, the accused should have the benefit of the doubt, because the judge ought to be more inclined to acquit than to condemn, except perhaps in favorable suits, such as a pleading for liberty and the like. If, however, the witnesses for the same side disagree, the judge ought to use his own discretion in discerning which side to favor, by considering either the number of witnesses, or their standing, or the favorableness of the suit, or the nature of the business and of the evidence Much more ought the evidence of one witness to be rejected if he contradict himself when questioned about what he has seen and about what he knows; not, however, if he contradict himself when questioned about matters of opinion and report, since he may be moved to answer differently according to the different things he has seen and heard. On the other hand if there be discrepancy of evidence in circumstances not touching the substance of the fact, for instance, whether the weather were cloudy or fine, whether the house were painted or not, or such like matters, such discrepancy does not weaken the evidence, because men are not wont to take much notice of such things, wherefore they easily forget them. Ondeed, a discrepancy of this kind renders the evidence more credible, as Chrysostom states (Hom. i in Matth.), because if the witnesses agreed in every point, even in the minutest of details, they would seem to have conspired together to say the same thing: but this must be left to the prudent discernment of the judge.
IIª-IIae q. 70 a. 2 ad 3 Ad tertium dicendum quod illud locum habet specialiter in episcopis, presbyteris, diaconibus et clericis Ecclesiae Romanae, propter eius dignitatem. Et hoc triplici ratione. Primo quidem, quia in ea tales institui debent quorum sanctitati plus credatur quam multis testibus. Secundo, quia homines qui habent de aliis iudicare, saepe, propter iustitiam, multos adversarios habent. Unde non est passim credendum testibus contra eos, nisi magna multitudo conveniat. Tertio, quia ex condemnatione alicuius eorum derogaretur in opinione hominum dignitati illius Ecclesiae et auctoritati. Quod est periculosius quam in ea tolerare aliquem peccatorem, nisi valde publicum et manifestum, de quo grave scandalum oriretur.	Reply to Objection 3. This passage refers specially to the bishops, priests, deacons and clerics of the Roman Church, on account of its dignity: and this for three reasons. First because in that Church those men ought to be promoted whose sanctity makes their evidence of more weight than that of many witnesses. Secondly, because those who have to judge other men, often have many opponents on account of their justice, wherefore those who give evidence against them should not be believed indiscriminately, unless they be very numerous. Thirdly, because the condemnation of any one of them would detract in public opinion from the dignity and authority of that Church, a result which would be more fraught with danger than if one were to tolerate a sinner in that same Church, unless he were very notorious and manifest, so that a grave scandal would arise if he were tolerated.
IIª-IIae q. 70 a. 3 arg. 1 Ad tertium sic proceditur. Videtur quod alicuius testimonium non sit repellendum nisi propter culpam. Quibusdam enim in poenam infligitur quod ad testimonium non admittantur, sicut patet in his qui infamia notantur. Sed poena non est inferenda nisi pro culpa. Ergo videtur quod nullius testimonium debeat repelli nisi propter culpam.	Objection 1. It would seem that a man's evidence ought not to be rejected except on account of some fault. For it a penalty on some that their evidence is inadmissible, as in the case of those who are branded with infamy. Now a penalty must not be inflicted save for a fault. Therefore it would seem that no man's evidence ought to be rejected save on account of a fault.
IIª-IIae q. 70 a. 3 arg. 2 Praeterea, de quolibet praesumendum est bonum, nisi appareat contrarium. Sed ad bonitatem hominis pertinet quod verum testimonium dicat. Cum ergo non possit constare de contrario nisi propter aliquam culpam, videtur quod nullius testimonium debeat repelli nisi propter culpam.	Objection 2. Further, "Good is to be presumed of every one, unless the contrary appear" [Cap. Dudum, de Praesumpt.]. Now it pertains to a man's goodness that he should give true evidence. Since therefore there can be no proof of the contrary, unless there be some fault of his, it would seem that no man's evidence should be rejected save for some fault.
IIª-IIae q. 70 a. 3 arg. 3 Praeterea, ad ea quae sunt de necessitate salutis nullus redditur non idoneus nisi propter peccatum. Sed testificari veritatem est de necessitate salutis, ut supra dictum est. Ergo nullus debet excludi a testificando nisi propter culpam.	Objection 3. Further, no man is rendered unfit for things necessary for salvation except by some sin. But it is necessary for salvation to give true evidence, as stated above (Article 1). Therefore no man should be excluded from giving evidence save for some fault.
IIª-IIae q. 70 a. 3 s. c. Sed contra est quod Gregorius dicit, et habetur II, qu. I, quia a servis suis accusatus est episcopus, sciendum est quod minime audiri debuerunt.	On the contrary, Gregory says (Regist. xiii, 44): "As to the bishop who is said to have been accused by his servants, you are to know that they should by no means have been heard": which words are embodied in the Decretals II, qu. 1, can. Imprimis.
IIª-IIae q. 70 a. 3 co. Respondeo dicendum quod testimonium, sicut dictum est, non habet infallibilem certitudinem, sed probabilem. Et ideo quidquid est quod probabilitatem afferat in contrarium, reddit testimonium inefficax. Redditur autem probabile quod aliquis in veritate testificanda non sit firmus, quandoque quidem propter culpam, sicut infideles, infames, item illi qui publico crimine rei sunt, qui nec accusare possunt, quandoque autem absque culpa. Et hoc vel ex defectu rationis, sicut patet in pueris, amentibus et mulieribus; vel ex affectu, sicut patet de inimicis et de personis coniunctis et domesticis; vel etiam ex exteriori conditione, sicut sunt pauperes, servi et illi quibus imperari potest, de quibus probabile est quod facile possint induci ad testimonium ferendum contra veritatem. Et sic patet quod testimonium alicuius repellitur et propter culpam, et absque culpa.	I answer that, As stated above (Article 2), the authority of evidence is not infallible but probable; and consequently the evidence for one side is weakened by whatever strengthens the probability of the other. Now the reliability of a person's evidence is weakened, sometimes indeed on account of some fault of his, as in the case of unbelievers and persons of evil repute, as well as those who are guilty of a public crime and who are not allowed even to accuse; sometimes, without any fault on his part, and this owing either to a defect in the reason, as in the case of children, imbeciles and women, or to personal feeling, as in the case of enemies, or persons united by family or household ties, or again owing to some external condition, as in the case of poor people, slaves, and those who are under authority, concerning whom it is to be presumed that they might easily be induced to give evidence against the truth. Thus it is manifest that a person's evidence may be rejected either with or without some fault of his.
IIª-IIae q. 70 a. 3 ad 1 Ad primum ergo dicendum quod repellere aliquem a testimonio magis pertinet ad cautelam falsi testimonii vitandi quam ad poenam. Unde ratio non sequitur.	Reply to Objection 1. If a person is disqualified from giving evidence this is done as a precaution against false evidence rather than as a punishment. Hence the argument does not prove.
IIª-IIae q. 70 a. 3 ad 2 Ad secundum dicendum quod de quolibet praesumendum est bonum nisi appareat contrarium, dummodo non vergat in periculum alterius. Quia tunc est adhibenda cautela, ut non de facili unicuique credatur, secundum illud I Ioan. IV, nolite credere omni spiritui.	Reply to Objection 2. Good is to be presumed of everyone unless the contrary appear, provided this does not threaten injury to another: because, in that case, one ought to be careful not to believe everyone readily, according to 1 John 4:1: "Believe not every spirit."
IIª-IIae q. 70 a. 3 ad 3 Ad tertium dicendum quod testificari est de necessitate salutis, supposita testis idoneitate et ordine iuris. Unde nihil prohibet aliquos excusari a testimonio ferendo, si non reputentur idonei secundum iura.	Reply to Objection 3. To give evidence is necessary for salvation, provided the witness be competent, and the order of justice observed. Hence nothing hinders certain persons being excused from giving evidence, if they be considered unfit according to law.
IIª-IIae q. 70 a. 4 arg. 1 Ad quartum sic proceditur. Videtur quod falsum testimonium non semper sit peccatum mortale. Contingit enim aliquem falsum testimonium ferre ex ignorantia facti. Sed talis ignorantia excusat a peccato mortali. Ergo testimonium falsum non semper est peccatum mortale.	Objection 1. It would seem that it is not always a mortal sin to give false evidence. For a person may happen to give false evidence, through ignorance of fact. Now such ignorance excuses from mortal sin. Therefore the giving of false evidence is not always a mortal sin.
IIª-IIae q. 70 a. 4 arg. 2 Praeterea, mendacium quod alicui prodest et nulli nocet, est officiosum, quod non est peccatum mortale. Sed quandoque in falso testimonio est tale mendacium, puta cum aliquis falsum testimonium perhibet ut aliquem a morte liberet, vel ab iniusta sententia quae intentatur per alios falsos testes vel per iudicis perversitatem. Ergo tale falsum testimonium non est peccatum mortale.	Objection 2. Further, a lie that benefits someone and hurts no man is officious, and this is not a mortal sin. Now sometimes a lie of this kind occurs in false evidence, as when a person gives false evidence in order to save a man from death, or from an unjust sentence which threatens him through other false witnesses or a perverse judge. Therefore in such cases it is not a mortal sin to give false evidence.
IIª-IIae q. 70 a. 4 arg. 3 Praeterea, iuramentum a teste requiritur ut timeat peccare mortaliter deierando. Hoc autem non esset necessarium si ipsum falsum testimonium esset peccatum mortale. Ergo falsum testimonium non semper est peccatum mortale.	Objection 3. Further, a witness is required to take an oath in order that he may fear to commit a mortal sin of perjury. But this would not be necessary, if it were already a mortal sin to give false evidence. Therefore the giving of false evidence is not always mortal sin.
IIª-IIae q. 70 a. 4 s. c. Sed contra est quod dicitur Prov. XIX, falsus testis non erit impunitus.	On the contrary, It is written (Proverbs 19:5): "A false witness shall not be unpunished."
IIª-IIae q. 70 a. 4 co. Respondeo dicendum quod falsum testimonium habet triplicem deformitatem. Uno modo, ex periurio, quia testes non admittuntur nisi iurati. Et ex hoc semper est peccatum mortale. Alio modo, ex violatione iustitiae. Et hoc modo est peccatum mortale in suo genere, sicut et quaelibet iniustitia. Et ideo in praecepto Decalogi sub hac forma interdicitur falsum testimonium, cum dicitur Exod. XX, non loquaris contra proximum tuum falsum testimonium, non enim contra aliquem facit qui eum ab iniuria facienda impedit, sed solum qui ei suam iustitiam tollit. Tertio modo, ex ipsa falsitate, secundum quod omne mendacium est peccatum. Et ex hoc non habet falsum testimonium quod semper sit peccatum mortale.	I answer that, False evidence has a threefold deformity. The first is owing to perjury, since witnesses are admitted only on oath and on this count it is always a mortal sin. Secondly, owing to the violation of justice, and on this account it is a mortal sin generically, even as any kind of injustice. Hence the prohibition of false evidence by the precept of the decalogue is expressed in this form when it is said (Exodus 20:16), "Thou shalt not bear false witness against thy neighbor." For one does nothing against a man by preventing him from doing someone an injury, but only by taking away his justice. Thirdly, owing to the falsehood itself, by reason of which every lie is a sin: on this account, the giving of false evidence is not always a mortal sin.
IIª-IIae q. 70 a. 4 ad 1 Ad primum ergo dicendum quod in testimonio ferendo non debet homo pro certo asserere, quasi sciens, id de quo certus non est, sed dubium debet sub dubio proferre, et id de quo certus est pro certo asserere. Sed quia contingit ex labilitate humanae memoriae quod reputat se homo quandoque certum esse de eo quod falsum est, si aliquis, cum debita sollicitudine recogitans, existimet se certum esse de eo quod falsum est, non peccat mortaliter hoc asserens, quia non dicit falsum testimonium per se et ex intentione, sed per accidens, contra id quod intendit.	Reply to Objection 1. In giving evidence a man ought not to affirm as certain, as though he knew it, that about which he is not certain and he should confess his doubt in doubtful terms, and that which he is certain about, in terms of certainty. Owing however to the frailty of the human memory, a man sometimes thinks he is certain about something that is not true; and then if after thinking over the matter with due care he deems himself certain about that false thing, he does not sin mortally if he asserts it, because the evidence which he gives is not directly an intentionally, but accidentally contrary to what he intends.
IIª-IIae q. 70 a. 4 ad 2 Ad secundum dicendum quod iniustum iudicium iudicium non est. Et ideo ex vi iudicii falsum testimonium in iniusto iudicio prolatum ad iniustitiam impediendam, non habet rationem peccati mortalis, sed solum ex iuramento violato.	Reply to Objection 2. An unjust judgment is not a judgment, wherefore the false evidence given in an unjust judgment, in order to prevent injustice is not a mortal sin by virtue of the judgment, but only by reason of the oath violated.
IIª-IIae q. 70 a. 4 ad 3 Ad tertium dicendum quod homines maxime abhorrent peccata quae sunt contra Deum, quasi gravissima, inter quae est periurium. Non autem ita abhorrent peccata quae sunt contra proximum. Et ideo ad maiorem certitudinem testimonii, requiritur testis iuramentum.	Reply to Objection 3. Men abhor chiefly those sins that are against God as being most grievous, and among them is perjury: whereas they do not abhor so much sins against their neighbor. Consequently, for the greater certitude of evidence, the witness is required to take a oath.