A Dictionary of Islam / Being a cyclopedia of the doctrines, rites, ceremonies, and customs, together with the technical and theological terms, of the Muhammadan religion.

by Thomas Patrick Hughes

The Mosaic law admitted expiation in the case of rash or forgotten oaths, vide [Lev. v. 4], but the Yamīnu ʾl-munʿaqid of Muḥammadan law allows a much greater latitude, for it applies to all vows or oaths excepting those intentionally false made with regard to future events.

The teaching of Muḥammadan jurists on the subject of oaths and vows, exhibits that reservatio mentalis of Muḥammadan morality which is so similar to that of the Jewish Rabbis, and which was condemned by Jesus Christ in [St. Matt. xxiii. 16].

Sunnī writers on jurisprudence say that an oath should be expressed by such attributes of the Deity as are commonly used in swearing, such as the power, or the glory, or the might of God, because an oath is usually expressed under one or other of those qualities; and the sense of yamīn, viz. “strength,” is by this means obtained, since as the swearer believes in the power, glory, and might, and other attributes of the Deity, it follows that the mention of these attributes only is sufficient to strengthen the resolution in the performance of the act vowed, or the avoidance thereof.

If a man swear “by the knowledge of God,” it does not constitute an oath, because an oath expressed by the knowledge of God is not in use; moreover, by “knowledge” is frequently implied merely that which is known; and in this sense the word knowledge is not expressive either of the name of God, of any of His attributes. In the same manner, should a person swear “by the wrath of God,” or “by the mercy of God,” it does not constitute an oath, because an oath is not commonly expressed by any of these attributes; moreover, by the word raḥmah is sometimes understood “rain,” and “heaven” is also occasionally expressed by that term; and by the word G͟haiz̤ is understood “punishment”; and none of these are either appellations or attributes of the Deity.

If a person swear by another name than that of God,—such as “the Prophet,” or “the Holy Temple,” this does not constitute an oath, as the Prophet has said, “if any man among you take an oath, he must swear by the name of God, or else his oath is void.” If a person swear by the Qurʾān, it does not constitute an oath, although the Qurʾān be the word of God, because men do not swear by the Qurʾān. The compiler of the Hidāyah observes that this is where the swearer only says, “by the Prophet,” or “by the Temple,” or “by the Qurʾān,” but if the swearer say, “If I act contrary to what I now say, may I be deprived ‘of the Prophet,’ ” or “of the temple,” or “of the Qurʾān,” this constitutes an oath, because such privation would reduce the swearer to the state of an infidel, and the suspension of infidelity upon a condition amounts to yamīn.

Abū Ḥanīfah alleges that if a man should swear “by the truth of God,” this does not constitute an oath, and in this Imām Muḥammad coincides. There are two opinions of Abū Yūsuf recorded on this point. According to one, it is not an oath; but according to the other it is an oath, because truth is one of the attributes of the Deity, signifying the certainty of the divine existence, and hence it is the same as if the swearer were to say, “by God, the truth!” and as oaths are common under this mode of expression, so an oath is hereby constituted. The argument of Imām Muḥammad and Abū Ḥanīfah is that the term “the truth,” as here expressed, relates merely to the identity of the godhead as the object of obedience, and hence an oath thus expressed appears to be taken by that which is neither an appellation nor an attribute of God. The learned jurists, however, say that if a person express himself thus, “by the truth I will do so and so,” this constitutes an oath, because the truth is one of the appellatives or proper names of God. But if a person were to say, “I will do this truly,” it does not amount to an oath, because the word truly can only be taken, in this case, as a corroboration or confirmation of the promise contained in the speech, being the same as if he were to say, “I shall do this indeed.” If a man say, “I swear,” or “I vow,” or “I testify,” whether the words “by God” be superadded or not, it constitutes an oath, because such words are commonly used in swearing; the use of them in the present tense is undisputed; and they are also sometimes used in the future tense, where the context admits of a construction in the present; and attestation amounts to an oath, as in that sense it occurs in the sacred writings. Now swearing “by the name of God” is both customary and conformable to the divine ordinances, but without the name of God it is forbidden. When it so occurs, therefore, it must be construed into a lawful oath; hence some say that intention is not requisite in it; others, however, allege that the intention is essential, because the words here recited bear the construction of a promise, that is, they admit of being received as applying to the future, and also of being taken as a vow without the name of God.

If a person, speaking in the Persian language, were to say, “I swear by God,” it amounts to an oath, because here the idiom confines the expression solely to the present; but if he were to say simply, “I swear,” some allege that this does not constitute an oath. If he were to say, “I swear by the divorce of my wife,” this is not an oath, as an oath is not so expressed in practice.

If a man in swearing say “by the age” or “the existence of God,” it constitutes an oath, because the age or existence of God signifies his eternity, which is one of his attributes.

If a person should say, “If I do this may I be a Jew, or a Christian, or an infidel,” it constitutes an oath; because, as the swearer has made the condition a sign of infidelity, it follows that he is conscious of his obligation to avoid the condition; and this obligation is possible, by making it an oath, in such a way as to render unlawful to himself that which is lawful. And if the oath relate to anything which he has done in the time past, as if he were to say, “If I have done so may I be a Jew or an infidel,” and so forth, this is yamīnu ʾl-G͟hamūs, or “perjury.” The swearer is not, however, in this case made a Jew or an infidel, because the words “may I be an infidel,” and so forth, relate to some future indefinite period. Some, on the contrary, have alleged that he becomes actually as an infidel, because the penalty which the swearer imprecates upon himself relates to the present instant of his testimony, being the same as if he were to say, “I am a Jew,” &c. But the majority of doctors say, the swearer does not become a Jew or infidel in either of the cases, either in that of a vow with respect to the future, or an oath regarding the past, provided he consider this merely as a form of swearing. But if he believe that by thus swearing he fully subjects himself to the penalty expressed, he suffers accordingly, in either instance, because he appears consenting to infidelity, on account of having ventured upon a thing by the commission of which he conceives that he may be rendered an infidel.

If a person say, “If I do this, may the anger of God fall upon me,” this does not constitute a vow, as not being a customary mode of expression for that purpose. And so also, if a person were to say, “May I be an adulterer or a drunkard or an usurer,” because these are not generally understood or received as forms of swearing.