What our Lord says of swearing may have respect to the third commandment, in which we are forbidden to “take the name of the Lord our God in vain.” It had also been said, “Thou shalt not swear by my name falsely; neither shalt thou profane the name of thy God.” And again, “If a man vow a vow unto the Lord, or swear an oath to bind his soul with a bond, he shall not break his word, he shall do according to all that proceedeth out of his mouth.” To these passages, and to the construction which had been put upon them, our Lord seems to have alluded in what he here teaches.
Many have supposed that oaths of every kind are here forbidden, and therefore refuse in any form, or on any occasion, to take them. To determine this question, we must have recourse to the principles laid down at the outset of the sermon. “Think not that I am come to destroy the law or the prophets; I am not come to destroy, but to fulfil. For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled,” ver. 17, 18. The question is, then, whether oaths of any kind belonged to the law, or whether they arose from the false glosses of the elders? If the former, it was not Christ’s design to destroy them: but if the latter, it was. That they were a part of the Divine law, and not of merely human authority, is sufficiently manifest from Deut. 6:13, “Thou shalt fear the Lord thy God, and serve him, and shalt swear by his name.” Consequently, it was not our Lord’s design to destroy them.
If it be objected, that though Christ did not destroy the moral law, yet there were various precepts pertaining to the ceremonial and judicial laws of Israel which, on his appearance, ceased to be binding, and that oaths might be of this description,—I answer, In abolishing things which had been of Divine authority, he is never known to have cast reproach on them, or to have imputed the observance of them to evil. He could not therefore be said to have destroyed even the ceremonial law, but rather to have fulfilled it. But the oaths against which he inveighs are expressly said to come of evil; and therefore could never have been of Divine authority.
To this may be added, If all oaths be unlawful under the gospel dispensation, some of the most solemn and impressive passages in the Epistles of Paul must be utterly wrong. “The God and Father of our Lord Jesus Christ, who is blessed for evermore, knoweth that I lie not—God is my witness, whom I serve in the gospel of his Son.” Each of these is an oath, and that of the most solemn kind; yet who ever thought of accusing the apostle of violating his Lord’s precept?
The truth appears to be this—the Jews had construed the commandment merely as a prohibition of perjury; accounting that if they did but swear truly as to matters of fact, or perform their oaths in case of promise, all was right. They seem to have had no idea, or at most but a very faint one, of sinning by swearing lightly. But for an oath to be lawful, it required, not only that the affirmation were true, or the vow performed; but that such a mode of affirming or vowing were necessary. This is evident from the words of the Divine precept, “Thou shalt not swear by my name falsely, neither shalt thou profane the name of thy God.” Thousands of things are true which yet it would be profaning the name of God to swear to. Here lay the sin which it was the design of Christ to reprove. He did not censure his countrymen for what was said before a magistrate, to put an end to strife; but for what passed in their ordinary communications (ver. 37); that is, for light and unnecessary oaths, by which the name of God was profaned. This was a sin so prevalent among the Jews, that even Christians, who were called from among them, stood in need of being warned against it, James 5:12.
It may appear rather extraordinary that any person who fears God should stand in need of these warnings; and if profane swearing were confined to expressly naming the name of God, they might be in general unnecessary among persons who had any claim to seriousness of character. But as both Jews and Christians have learned to mince and soften their oaths, by leaving out the name of God, while yet it is implied, and consequently profaned, such warnings cannot be considered as superfluous We perceive by our Lord’s words that it was common among the Jews to swear “by heaven, by earth, by Jerusalem, by the temple, by the altar, by their own head,” &c. &c. They had also some curious distinctions between swearing by the temple, and by the gold of the temple; the altar, and the gift upon the altar; but our Lord, looking deep into the principles of things, considers them all as amounting to the same thing—the profanation of God’s holy name, Matt. 23:16–22.
It is thus that oaths are used among men calling themselves Christians In popish countries, your ears are continually stunned by hearing people swear, not only by their saints, but by Jesus, by his blood and his wounds; and even in protestant countries, these terrible oaths are turned into exclamations on many a trivial occasion. The words ’S blood, ’S wounds, &c., are no other than these old popish oaths minced, or contracted by the dread of expressly naming the blood and wounds of Christ. Every person who uses such language may not be apprised of the meaning; but every thing of the kind cometh of evil. The same may be said of all such phrases as the following—Of faith, By my troth, Upon my soul, Upon my life, Upon my honour, Upon my word. By our Lord’s exposition of such language, in Matt. 23:16–22, all these modes of speaking would be found to bear a relation to God, and so to be a profaning of his name.
How opposite to all this profane jargon is the simple and dignified language prescribed by our Lord!—“Let your communication be, Yea, yea; Nay, nay; for whatsoever is more than these cometh of evil.” He that is conscious of a want of veracity may find it necessary to confirm his words with oaths; but he that habitually speaketh the truth will have no occasion for resorting to such mean and profane expedients.
Fuller, A. G. (1988). “Oaths,” Illustrations from Scripture: Sermon on the Mount. The Complete Works of Andrew Fuller: Memoirs, Sermons, Etc. (J. Belcher, Ed.; Vol. 1, pp. 570–571). Sprinkle Publications.
