Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that theft is not always a sin. For no sin is commanded by God, since it is written (Ecclus. 15:21): "He hath commanded no man to do wickedly." Yet we find that God commanded theft, for it is written (Ex. 12:35,36): "And the children of Israel did as the Lord had commanded Moses . . . and they stripped the Egyptians." Therefore theft is not always a sin.

Objection 2: Further, if a man finds a thing that is not his and takes it, he seems to commit a theft, for he takes another's property. Yet this seems lawful according to natural equity, as the jurists hold. Therefore it seems that theft is not always a sin.

Objection 3: Further, he that takes what is his own does not seem to sin, because he does not act against justice, since he does not destroy its equality. Yet a man commits a theft even if he secretly take his own property that is detained by or in the safe-keeping of another. Therefore it seems that theft is not always a sin.

On the contrary, It is written (Ex. 20:15): "Thou shalt not steal."

I answer that, If anyone consider what is meant by theft, he will find that it is sinful on two counts. First, because of its opposition to justice, which gives to each one what is his, so that for this reason theft is contrary to justice, through being a taking of what belongs to another. Secondly, because of the guile or fraud committed by the thief, by laying hands on another's property secretly and cunningly. Wherefore it is evident that every theft is a sin.

Reply to Objection 1: It is no theft for a man to take another's property either secretly or openly by order of a judge who has commanded him to do so, because it becomes his due by the very fact that it is adjudicated to him by the sentence of the court. Hence still less was it a theft for the Israelites to take away the spoils of the Egyptians at the command of the Lord, Who ordered this to be done on account of the ill-treatment accorded to them by the Egyptians without any cause: wherefore it is written significantly (Wis. 10:19): "The just took the spoils of the wicked."

Reply to Objection 2: With regard to treasure-trove a distinction must be made. For some there are that were never in anyone's possession, for instance precious stones and jewels, found on the seashore, and such the finder is allowed to keep . The same applies to treasure hidden underground long since and belonging to no man, except that according to civil law the finder is bound to give half to the owner of the land, if the treasure trove be in the land of another person . Hence in the parable of the Gospel (Mt. 13:44) it is said of the finder of the treasure hidden in a field that he bought the field, as though he purposed thus to acquire the right of possessing the whole treasure. On the other Land the treasure-trove may be nearly in someone's possession: and then if anyone take it with the intention, not of keeping it but of returning it to the owner who does not look upon such things as unappropriated, he is not guilty of theft. In like manner if the thing found appears to be unappropriated, and if the finder believes it to be so, although he keep it, he does not commit a theft . In any other case the sin of theft is committed : wherefore Augustine says in a homily (Serm. clxxviii; De Verb. Apost.): "If thou hast found a thing and not returned it, thou hast stolen it" (Dig. xiv, 5, can. Si quid invenisti).

Reply to Objection 3: He who by stealth takes his own property which is deposited with another man burdens the depositary, who is bound either to restitution, or to prove himself innocent. Hence he is clearly guilty of sin, and is bound to ease the depositary of his burden. On the other hand he who, by stealth, takes his own property, if this be unjustly detained by another, he sins indeed; yet not because he burdens the retainer, and so he is not bound to restitution or compensation: but he sins against general justice by disregarding the order of justice and usurping judgment concerning his own property. Hence he must make satisfaction to God and endeavor to allay whatever scandal he may have given his neighbor by acting this way.

Articulus 5

Argumentum 1

Ad quintum sic proceditur. Videtur quod furtum non semper sit peccatum. Nullum enim peccatum cadit sub praecepto divino, dicitur enim Eccli. XV, nemini mandavit impie agere.

Sed deus invenitur praecepisse furtum, dicitur enim Exod. XII, fecerunt filii Israel sicut praeceperat dominus Moysi, et expoliaverunt Aegyptios.

Ergo furtum non semper est peccatum.

Argumentum 2

Praeterea, ille qui invenit rem non suam, si eam accipiat, videtur furtum committere, quia accipit rem alienam. Sed hoc videtur esse licitum secundum naturalem aequitatem; ut iuristae dicunt.

Ergo videtur quod furtum non semper sit peccatum.

Argumentum 3

Praeterea, ille qui accipit rem suam non videtur peccare, cum non agat contra iustitiam, cuius aequalitatem non tollit.

Sed furtum committitur etiam si aliquis rem suam occulte accipiat ab altero detentam vel custoditam.

Sed Contra

Sed contra est quod dicitur Exod. XX, non furtum facies.

Corpus

Respondeo dicendum quod si quis consideret furti rationem, duas rationes peccati in eo inveniet. Primo quidem, propter contrarietatem ad iustitiam, quae reddit unicuique quod suum est.

Et sic furtum iustitiae opponitur, inquantum furtum est acceptio rei alienae. Secundo, ratione doli seu fraudis, quam fur committit occulte et quasi ex insidiis rem alienam usurpando.

Unde manifestum est quod omne furtum est peccatum.

Ad 1

Ad primum ergo dicendum quod accipere rem alienam vel occulte vel manifeste auctoritate iudicis hoc decernentis, non est furtum, quia iam fit sibi debitum per hoc quod sententialiter sibi est adiudicatum. Unde multo minus furtum fuit quod filii Israel tulerunt spolia Aegyptiorum de praecepto domini hoc decernentis pro afflictionibus quibus Aegyptii eos sine causa afflixerant.

Et ideo signanter dicitur Sap. X, iusti tulerunt spolia impiorum.

Ad 2

Ad secundum dicendum quod circa res inventas est distinguendum.

Quaedam enim sunt quae nunquam fuerunt in bonis alicuius, sicut lapilli et gemmae quae inveniuntur in littore maris, et talia occupanti conceduntur. Et eadem ratio est de thesauris antiquo tempore sub terra occultatis, quorum non est aliquis possessor, nisi quod secundum leges civiles tenetur inventor medietatem dare domino agri, si in alieno agro invenerit; propter quod in parabola evangelii dicitur, Matth. XIII, de inventore thesauri absconditi in agro, quod emit agrum, quasi ut haberet ius possidendi totum thesaurum. Quaedam vero res inventae fuerunt de propinquo in alicuius bonis. Et tunc, si quis eas accipiat non animo retinendi, sed animo restituendi domino, qui eas pro derelictis non habet, non committit furtum. Et similiter si pro derelictis habeantur, et hoc credat inventor, licet sibi retineat, non committit furtum.

Alias autem committitur peccatum furti.

Unde Augustinus dicit, in quadam homilia, et habetur XIV, qu. V, si quid invenisti et non reddidisti, rapuisti.

Ad 3

Ad tertium dicendum quod ille qui furtim accipit rem suam apud alium depositam, gravat depositarium, quia tenetur ad restituendum, vel ad ostendendum se esse innoxium. Unde manifestum est quod peccat, et tenetur ad relevandum gravamen depositarii. Qui vero furtim accipit rem suam apud alium iniuste detentam, peccat quidem, non quia gravet eum qui detinet, et ideo non tenetur ad restituendum aliquid vel ad recompensandum, sed peccat contra communem iustitiam, dum ipse sibi usurpat suae rei iudicium, iuris ordine praetermisso. Et ideo tenetur deo satisfacere, et dare operam ut scandalum proximorum, si inde exortum fuerit, sedetur.