We have here an exposition of the third commandment, which we are the more concerned right to understand, because it is particularly said, that God will not hold him guiltless, however he may hold himself, who breaks this commandment, by taking the name of the Lord in vain. Now as to this command,

I.It is agreed on all hands that it forbids perjury, forswearing, and the violation of oaths and vows, Mat 5:33. This was said to them of old time, and is the true intent and meaning of the third commandment. Thou shalt not use, or take up, the name of God (as we do by an oath) in vain, or unto vanity, or a lie. He hath not lift up his soul unto vanity, is expounded in the next words, nor sworn deceitfully, Psa 24:4. Perjury is a sin condemned by the light of nature, as a complication of impiety toward God and injustice toward man, and as rendering a man highly obnoxious to the divine wrath, which was always judged to follow so infallibly upon that sin, that the forms of swearing were commonly turned into execrations or imprecations; as that, God do so to me, and more also; and with us, So help me God; wishing I may never have any help from God, if I swear falsely. Thus, by the consent of nations, have men cursed themselves, not doubting but that God would curse them, if they lied against the truth then, when they solemnly called God to witness to it.

It is added, from some other scriptures, but shalt perform unto the Lord thine oaths (Num 30:2); which may be meant, either, 1. Of those promises to which God is a party, vows made to God; these must be punctually paid (Ecc 5:4, Ecc 5:5): or, 2. Of those promises made to our brethren, to which God was a Witness, he being appealed to concerning our sincerity; these must be performed to the Lord, with an eye to him, and for his sake: for to him, by ratifying the promises with an oath, we have made ourselves debtors; and if we break a promise so ratified, we have not lied unto men only, but unto God.

II.It is here added, that the commandment does not only forbid false swearing, but all rash, unnecessary swearing: Swear not at all, Mat 5:34; Compare Jam 5:12. Not that all swearing is sinful; so far from that, if rightly done, it is a part of religious worship, and we in it give unto God the glory due to his name. See Deu 6:13; Deu 10:20; Isa 45:23; Jer 4:2. We find Paul confirming what he said by such solemnities (Co2 1:23), when there was a necessity for it. In swearing, we pawn the truth of something known, to confirm the truth of something doubtful or unknown; we appeal to a greater knowledge, to a higher court, and imprecate the vengeance of a righteous Judge, if we swear deceitfully.

Now the mind of Christ in this matter is,

1.That we must not swear at all, but when we are duly called to it, and justice or charity to our brother, or respect to the commonwealth, make it necessary for the end of strife (Heb 6:16), of which necessity the civil magistrate is ordinarily to be the judge. We may be sworn, but we must now swear; we may be adjured, and so obliged to it, but we must not thrust ourselves upon it for our own worldly advantage.

2.That we must not swear lightly and irreverently, in common discourse: it is a very great sin to make a ludicrous appeal to the glorious Majesty of heaven, which, being a sacred thing, ought always to be very serious: it is a gross profanation of God's holy name, and of one of the holy things which the children of Israel sanctify to the Lord: it is a sin that has no cloak, no excuse for it, and therefore a sign of a graceless heart, in which enmity to God reigns: Thine enemies take thy name in vain.

3.That we must in a special manner avoid promissory oaths, of which Christ more particularly speaks here, for they are oaths that are to be performed. The influence of an affirmative oath immediately ceases, when we have faithfully discovered the truth, and the whole truth; but a promissory oath binds so long, and may be so many ways broken, by the surprise as well as strength of a temptation, that it is not to be used but upon great necessity: the frequent requiring and using of oaths, is a reflection upon Christians, who should be of such acknowledged fidelity, as that their sober words should be as sacred as their solemn oaths.

4.That we must not swear by any other creature. It should seem there were some, who, in civility (as they thought) to the name of God, would not make use of that in swearing, but would swear by heaven or earth, etc. This Christ forbids here (Mat 5:34) and shows that there is nothing we can swear by, but it is some way or other related to God, who is the Fountain of all beings, and therefore that it is as dangerous to swear by them, as it is to swear by God himself: it is the verity of the creature that is laid at stake; now that cannot be an instrument of testimony, but as it has regard to God, who is the summum verum - the chief Truth. As for instance,

(1)Swear not by the heaven; "As sure as there is a heaven, this is true;" for it is God's throne, where he resides, and in a particular manner manifests his glory, as a Prince upon his throne: this being the inseparable dignity of the upper world, you cannot swear by heaven, but you swear by God himself.

(2)Nor by the earth, for it is his footstool. He governs the motions of this lower world; as he rules in heaven, so he rules over the earth; and though under his feet, yet it is also under his eye and care, and stands in relation to him as his, Psa 24:1. The earth is the Lord's; so that in swearing by it, you swear by its Owner.

(3)Neither by Jerusalem, a place for which the Jews had such a veneration, that they could not speak of any thing more sacred to swear by; but beside the common reference Jerusalem has to God, as part of the earth, it is in special relation to him, for it is the city of the great King (Psa 48:2), the city of God (Psa 46:4), he is therefore interested in it, and in every oath taken by it.

(4)"Neither shalt thou swear by the head; though it be near thee, and an essential part of thee, yet it is more God's than thine; for he made it, and formed all the springs and powers of it; whereas thou thyself canst not, from any natural intrinsic influence, change the colour of one hair, so as to make it white or black; so that thou canst not swear by thy head, but thou swearest by him who is the Life of thy head, and the Lifter up of it." Psa 3:3.

5.That therefore in all our communications we must content ourselves with, Yea, yea, and nay, nay, Mat 5:37. In ordinary discourse, if we affirm a thing, let us only say, Yea, it is so; and, if need be, to evidence our assurance of a thing, we may double it, and say, Yea, yea, indeed it is so: Verily, verily, was our Saviour's yea, yea. So if we deny a thing, let is suffice to say, No; or if it be requisite, to repeat the denial, and say, No, no; and if our fidelity be known, that will suffice to gain us credit; and if it be questioned, to back what we say with swearing and cursing, is but to render it more suspicious. They who can swallow a profane oath, will not strain at a lie. It is a pity that this, which Christ puts in the mouths of all his disciples, should be fastened, as a name of reproach, upon a sect faulty enough other ways, when (as Dr. Hammond says) we are not forbidden any more than yea and nay, but are in a manner directed to the use of that.

The reason is observable; For whatsoever is more than these cometh of evil, though it do not amount to the iniquity of an oath. It comes ek tou Diabolou; so an ancient copy has it: it comes from the Devil, the evil one; it comes from the corruption of men's nature, from passion and vehemence; from a reigning vanity in the mind, and a contempt of sacred things: it comes from that deceitfulness which is in men, All men are liars; therefore men use these protestations, because they are distrustful one of another, and think they cannot be believed without them. Note, Christians should, for the credit of their religion, avoid not only that which is in itself evil, but that which cometh of evil, and has the appearance of it. That may be suspected as a bad thing, which comes from a bad cause. An oath is physic, which supposes a disease.

Again, ye have heard that it hath been said,.... Besides what has been observed, in ver. 21 and 27 you know it has also been said,

by, or to them of old time, what is written in Lev 19:12. "And ye shall not swear by my name falsely"; which seems to be referred to, when it is said, "thou shalt not forswear thyself": and is the law forbidding perjury, or false swearing; and was what the Jews were chiefly, if not only concerned about; little regarding the vanity, only the truth of an oath: for they took swearing vainly, to be the same as swearing falsely; wherefore so long as what they swore was truth, they were not careful whether it was of any importance or not: moreover, these men sinned, in that they swore by the creatures, which they thought they might do, and not sin; and when they had so done, were not under obligation to perform; because they made no use of the name of God, to whom only vows and oaths were to be performed, "but shalt perform unto the Lord thine oaths", Num 30:2 which they understood of vows only made to the Lord, and not to others; and of oaths, when in his name, and not by others; which they did do, and yet thought themselves not obliged by them.

Again, ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself--These are not the precise words of Exo 20:7; but they express all that it was currently understood to condemn, namely, false swearing (Lev 19:12, &c.). This is plain from what follows.

But I say unto you, Swear not at all--That this was meant to condemn swearing of every kind and on every occasion--as the Society of Friends and some other ultra-moralists allege--is not for a moment to be thought. For even Jehovah is said once and again to have sworn by Himself; and our Lord certainly answered upon oath to a question put to Him by the high priest; and the apostle several times, and in the most solemn language, takes God to witness that he spoke and wrote the truth; and it is inconceivable that our Lord should here have quoted the precept about not forswearing ourselves, but performing to the Lord our oaths, only to give a precept of His own directly in the teeth of it. Evidently, it is swearing in common intercourse and on frivolous occasions that is here meant. Frivolous oaths were indeed severely condemned in the teaching of the times. But so narrow was the circle of them that a man might swear, says LIGHTFOOT, a hundred thousand times and yet not be guilty of vain swearing. Hardly anything was regarded as an oath if only the name of God were not in it; just as among ourselves, as TRENCH well remarks, a certain lingering reverence for the name of God leads to cutting off portions of His name, or uttering sounds nearly resembling it, or substituting the name of some heathen deity, in profane exclamations or asseverations. Against all this our Lord now speaks decisively; teaching His audience that every oath carries an appeal to God, whether named or not.

neither by heaven; for it is God's throne--(quoting Isa 66:1);