Of Oaths

Of Oaths — St. Thomas Aquinas asks: Whether to swear is to call God to witness?; Whether it is lawful to swear?; Whether three accompanying conditions of an oath are suitably assigned, namely, justice, judgment, and truth?; Whether an oath is an act of religion or latria?; Whether oaths are desirable and to be used frequently as something useful and good?; Whether it is lawful to swear by creatures?; Whether an oath has a binding force?; Whether an oath is more binding than a vow?; Whether anyone can dispense from an oath?; Whether an oath is voided by a condition of person or time?.

We must now consider those external acts of religion, whereby something Divine is taken by man: and this is either a sacrament or the Name of God. The place for treating of the taking of a sacrament will be in the Third Part of this work: of the taking of God's Name we shall treat now. The Name of God is taken by man in three ways. First, by way of oath in order to confirm one's own assertion: secondly, by way of adjuration as an inducement to others: thirdly, by way of invocation for the purpose of prayer or praise. Accordingly we must first treat of oaths: and under this head there are ten points of inquiry:

Article 1: Whether to swear is to call God to witness?

Augustine says in a sermon on perjury (Serm. clxxx): "When a man says: 'By God,' what else does he mean but that God is his witness?"

As the Apostle says (Heb. 6:16), oaths are taken for the purpose of confirmation. Now speculative propositions receive confirmation from reason, which proceeds from principles known naturally and infallibly true. But particular contingent facts regarding man cannot be confirmed by a necessary reason, wherefore propositions regarding such things are wont to be confirmed by witnesses. Now a human witness does not suffice to confirm such matters for two reasons. First, on account of man's lack of truth, for many give way to lying, according to Ps. 16:10, "Their mouth hath spoken lies [Vulg.: 'proudly']." Secondly, on account of this lack of knowledge, since he can know neither the future, nor secret thoughts, nor distant things: and yet men speak about such things, and our everyday life requires that we should have some certitude about them. Hence the need to have recourse to a Divine witness, for neither can God lie, nor is anything hidden from Him. Now to call God to witness is named "jurare" [to swear] because it is established as though it were a principle of law [jure] that what a man asserts under the invocation of God as His witness should be accepted as true. Now sometimes God is called to witness when we assert present or past events, and this is termed a "declaratory oath"; while sometimes God is called to witness in confirmation of something future, and this is termed a "promissory oath." But oaths are not employed in order to substantiate necessary matters, and such as come under the investigation of reason; for it would seem absurd in a scientific discussion to wish to prove one's point by an oath.

Article 2: Whether it is lawful to swear?

It is written (Dt. 6:13): "Thou shalt fear the Lord thy God . . . and shalt swear by His name."

Nothing prevents a thing being good in itself, and yet becoming a source of evil to one who makes use thereof unbecomingly: thus to receive the Eucharist is good, and yet he that receives it "unworthily, eateth and drinketh judgment to himself" (1 Cor. 11:29). Accordingly in answer to the question in point it must be stated that an oath is in itself lawful and commendable. This is proved from its origin and from its end. From its origin, because swearing owes its introduction to the faith whereby man believes that God possesses unerring truth and universal knowledge and foresight of all things: and from its end, since oaths are employed in order to justify men, and to put an end to controversy (Heb. 6:16).

Yet an oath becomes a source of evil to him that makes evil use of it, that is who employs it without necessity and due caution. For if a man calls God as witness, for some trifling reason, it would seemingly prove him to have but little reverence for God, since he would not treat even a good man in this manner. Moreover, he is in danger of committing perjury, because man easily offends in words, according to James 3:2, "If any man offend not in word, the same is a perfect man." Wherefore it is written (Ecclus. 23:9): "Let not thy mouth be accustomed to swearing, for in it there are many falls."

Article 3: Whether three accompanying conditions of an oath are suitably assigned, namely, justice, judgment, and truth?

It is written (Jer. 4:2): "Thou shalt swear: As the Lord liveth, in truth, and in judgment, and in justice": which words Jerome expounds, saying: "Observe that an oath must be accompanied by these conditions, truth, judgment and justice."

As stated above (), an oath is not good except for one who makes good use of it. Now two conditions are required for the good use of an oath. First, that one swear, not for frivolous, but for urgent reasons, and with discretion; and this requires judgment or discretion on the part of the person who swears. Secondly, as regards the point to be confirmed by oath, that it be neither false, nor unlawful, and this requires both truth, so that one employ an oath in order to confirm what is true, and justice, so that one confirm what is lawful. A rash oath lacks judgment, a false oath lacks truth, and a wicked or unlawful oath lacks justice.

Article 4: Whether an oath is an act of religion or latria?

It is written (Dt. 6:13): "Thou shalt fear the Lord thy God, and shalt serve Him only, and thou shalt swear by His name." Now he speaks there of the servitude of religion. Therefore swearing is an act of religion.

As appears from what has been said above (), he that swears calls God to witness in confirmation of what he says. Now nothing is confirmed save by what is more certain and more powerful. Therefore in the very fact that a man swears by God, he acknowledges God to be more powerful, by reason of His unfailing truth and His universal knowledge; and thus in a way he shows reverence to God. For this reason the Apostle says (Heb. 6:16) that "men swear by one greater than themselves," and Jerome commenting on Mat. 5:34, says that "he who swears either reveres or loves the person by whom he swears." The Philosopher, too, states (Metaph. i, 3) that "to swear is to give very great honor." Now to show reverence to God belongs to religion or latria. wherefore it is evident that an oath is an act of religion or latria.

Article 5: Whether oaths are desirable and to be used frequently as something useful and good?

It is written (Ecclus. 23:12): "A man that sweareth much shall be filled with iniquity": and Augustine says (De Mendacio xv) that "the Lord forbade swearing, in order that for your own part you might not be fond of it, and take pleasure in seeking occasions of swearing, as though it were a good thing."

Whatever is required merely as a remedy for an infirmity or a defect, is not reckoned among those things that are desirable for their own sake, but among those that are necessary: this is clear in the case of medicine which is required as a remedy for sickness. Now an oath is required as a remedy to a defect, namely, some man's lack of belief in another man. Wherefore an oath is not to be reckoned among those things that are desirable for their own sake, but among those that are necessary for this life; and such things are used unduly whenever they are used outside the bounds of necessity. For this reason Augustine says (De Serm. Dom. in Monte i, 17): "He who understands that swearing is not to be held as a good thing," i.e. desirable for its own sake, "restrains himself as far as he can from uttering oaths, unless there be urgent need."

Article 6: Whether it is lawful to swear by creatures?

Joseph swore "by the health of Pharaoh" (Gn. 42:16). Moreover it is customary to swear by the Gospel, by relics, and by the saints.

As stated above (), there are two kinds of oath. One is uttered a simple contestation or calling God as witness: and this kind of oath, like faith, is based on God's truth. Now faith is essentially and chiefly about God Who is the very truth, and secondarily about creatures in which God's truth is reflected, as stated above (). In like manner an oath is chiefly referred to God Whose testimony is invoked; and secondarily an appeal by oath is made to certain creatures considered, not in themselves, but as reflecting the Divine truth. Thus we swear by the Gospel, i.e. by God Whose truth is made known in the Gospel; and by the saints who believed this truth and kept it.

The other way of swearing is by cursing and in this kind of oath a creature is adduced that the judgment of God may be wrought therein. Thus a man is wont to swear by his head, or by his son, or by some other thing that he loves, even as the Apostle swore (2 Cor. 1:23), saying: "I call God to witness upon my soul."

As to Joseph's oath by the health of Pharaoh this may be understood in both ways: either by way of a curse, as though he pledged Pharao's health to God; or by way of contestation, as though he appealed to the truth of God's justice which the princes of the earth are appointed to execute.

Article 7: Whether an oath has a binding force?

It is written (Mat. 5:33): "Thou shalt perform thy oaths to the Lord."

An obligation implies something to be done or omitted; so that apparently it regards neither the declaratory oath (which is about something present or past), nor such oaths as are about something to be effected by some other cause (as, for example, if one were to swear that it would rain tomorrow), but only such as are about things to be done by the person who swears.

Now just as a declaratory oath, which is about the future or the present, should contain the truth, so too ought the oath which is about something to be done by us in the future. Yet there is a difference: since, in the oath that is about the past or present, this obligation affects, not the thing that already has been or is, but the action of the swearer, in the point of his swearing to what is or was already true; whereas, on the contrary, in the oath that is made about something to be done by us, the obligation falls on the thing guaranteed by oath. For a man is bound to make true what he has sworn, else his oath lacks truth.

Now if this thing be such as not to be in his power, his oath is lacking in judgment of discretion: unless perchance what was possible when he swore become impossible to him through some mishap. as when a man swore to pay a sum of money, which is subsequently taken from him by force or theft. For then he would seem to be excused from fulfilling his oath, although he is bound to do what he can, as, in fact, we have already stated with regard to the obligation of a vow (). If, on the other hand, it be something that he can do, but ought not to, either because it is essentially evil, or because it is a hindrance to a good, then his oath is lacking in justice: wherefore an oath must not be kept when it involves a sin or a hindrance to good. For in either case "its result is evil" [*Cf. Bede, Homil. xix, in Decoll. S. Joan. Bapt.]

Accordingly we must conclude that whoever swears to do something is bound to do what he can for the fulfilment of truth; provided always that the other two accompanying conditions be present, namely, judgment and justice.

Article 8: Whether an oath is more binding than a vow?

A vow binds one to God while an oath sometimes binds one to man. Now one is more bound to God than to man. Therefore a vow is more binding than an oath.

The obligation both of vow and of an oath arises from something Divine; but in different ways. For the obligation of a vow arises from the fidelity we owe God, which binds us to fulfil our promises to Him. On the other hand, the obligation of an oath arises from the reverence we owe Him which binds us to make true what we promise in His name. Now every act of infidelity includes an irreverence, but not conversely, because the infidelity of a subject to his lord would seem to be the greatest irreverence. Hence a vow by its very nature is more binding than an oath.

Article 9: Whether anyone can dispense from an oath?

A vow is more binding than an oath, as stated above (). But a vow admits of dispensation and therefore an oath does also.

As stated above (), the necessity of a dispensation both from the law and from a vow arises from the fact that something which is useful and morally good in itself and considered in general, may be morally evil and hurtful in respect of some particular emergency: and such a case comes under neither law nor vow. Now anything morally evil or hurtful is incompatible with the matter of an oath: for if it be morally evil it is opposed to justice, and if it be hurtful it is contrary to judgment. Therefore an oath likewise admits of dispensation.

Article 10: Whether an oath is voided by a condition of person or time?

It is stated (II, qu. v, can. Si quis presbyter): "Let a priest be examined 'by his sacred consecration,' instead of being put on his oath": and (22, qu. v, can. Nullus): "Let no one in ecclesiastical orders dare to swear on the Holy Gospels to a layman."

Two things are to be considered in an oath. One is on the part of God, whose testimony is invoked, and in this respect we should hold an oath in the greatest reverence. For this reason children before the age of puberty are debarred from taking oaths [*Caus. XXII, qu. 5, can. Parvuli], and are not called upon to swear, because they have not yet attained the perfect use of reason, so as to be able to take a oath with due reverence. Perjurers also are debarred from taking an oath, because it is presumed from their antecedents that they will not treat an oath with the reverence due to it. For this same reason, in order that oaths might be treated with due reverence the law says (22, qu. v, can. Honestum): "It is becoming that he who ventures to swear on holy things should do so fasting, with all propriety and fear of God."

The other thing to be considered is on the part of the man, whose assertion is confirmed by oath. For a man's assertion needs no confirmation save because there is a doubt about it. Now it derogates from a person's dignity that one should doubt about the truth of what he says, wherefore "it becomes not persons of great dignity to swear." For this reason the law says (II, qu. v, can. Si quis presbyter) that "priests should not swear for trifling reasons." Nevertheless it is lawful for them to swear if there be need for it, or if great good may result therefrom. Especially is this the case in spiritual affairs, when moreover it is becoming that they should take oath on days of solemnity, since they ought then to devote themselves to spiritual matters. Nor should they on such occasions take oaths temporal matters, except perhaps in cases grave necessity.