For men, etc. It is an argument from the less to the greater; if credit is given to man, who is by nature false, when he swears, and for this reason, because he confirms what he says by God's name, how much more credit is due to God, who is eternal truth, when he swears by himself? Now he mentions several things to commend this declaration; and first he says that men swear by the greater; by which he means that they who are wanting in due authority borrow it from another. He adds that there is so much reverence in an oath that it suffices for confirmation, and puts an end to all disputes where the testimonies of men and other proofs are wanting. Then is not he a sufficient witness for himself whom all appeal to as a witness? Is he not to obtain credit for what he says, who, by his authority, removes all doubts among others? If God's name, pronounced by man's tongue, possesses so much superiority, how much more weight ought it to have, when God himself swears by his own name? Thus much as to the main point. But here in passing, two things are to be noticed, -- that we are to swear by God's name when necessity requires, and that Christians are allowed to make an oath, because it is a lawful remedy for removing contentions. God in express words bids us to swear by his name; if other names are blended with it, the oath is profaned. For this there are especially three reasons: when there is no way of bringing the truth to light, it is not right, for the sake of verifying it, to have recourse to any but to God, who is himself eternal truth; and then, since he alone knows the heart, his own office is taken from him, when in things hidden, of which men can form no opinion, we appeal to any other judge; and thirdly, because in swearing we not only appeal to him as a witness, but also call upon him as an avenger of perjury in case we speak falsely. It is no wonder, then, that he is so greatly displeased with those who swear by another name, for his own honor is thus disparaged. And that there are different forms often used in Scripture, makes nothing against this truth; for they did not swear by heaven or earth, as though they ascribed any divine power to them, or attributed to them the least portion of divinity, but by this indirect protestation, so to speak, they had a regard to the one true God. There are indeed various kinds of protestations; but the chief one is, when we refer to God as a judge and directly appeal to his judgmentseat; another is, when we name things especially dear to us as our life, or our head, or anything of this kind; and the third is, when we call creatures as witnesses before God. But in all these ways we swear properly by no other than by God. hence they betray their impiety no less than their ignorance, who contend that it is lawful to connect dead saints with God so as to attribute to them the right of punishing. Further, this passage teaches us, as it has been said, that an oath may be lawfully used by Christians; and this ought to be particularly observed, on account of fanatical men who are disposed to abrogate the practice of solemn swearing which God has prescribed in his Law. For certainly the Apostle speaks here of the custom of swearing as of a holy practice, and approved by God. Moreover, he does not say of it as having been formerly in use, but as of a thing still practiced. Let it then be employed as a help to find out the truth when other proofs are wanting.

For men verily swear by the greater - That is, they appeal to God. They never swear by one who is inferior to themselves. The object of the apostle in this declaration is to show that as far as this could be done it had been by God. He could not indeed swear by one greater than himself, but he could make his promise as certain as an oath taken by people was when they solemnly appealed to him. He could appeal to his own existence and veracity, which was at any time the most solemn form of an oath, and thus put the mind to rest in regard to the hope of heaven.
And an oath for confirmation - An oath taken to confirm or establish anything.
Is to them an end of all strife - That is, when two parties are at variance, or have a cause at issue, an oath binds them to adhere to the terms of agreement concluded on, or contracting parties bind themselves by a solemn oath to adhere to the conditions of an agreement, and this puts an end to all strife. They rest satisfied when a solemn oath has been taken, and they feel assured that the agreement will be complied with. Or it may refer to cases where a man was accused of wrong before a court, and where he took a solemn oath that the thing had not been done, and his oath was admitted to be sufficient to put an end to the controversy. The general meaning is clear, that in disputes between man and man, an appeal was made to an oath, and that was allowed to settle it. The connection here is, that as far as the case would admit of, the same thing was done by God. His oath by himself made his promise firm.

Men verily swear by the greater - One who has greater authority; who can take cognizance of the obligation, and punish the breach of it.
An oath for confirmation - "This observation teaches us," says Dr. Macknight, "that both promissory oaths concerning things lawful and in our power, and oaths for the confirmation of things doubtful, when required by proper authority, and taken religiously, are allowable under the Gospel."

For men verily swear by the greater,.... These words contain a reason why God swore by himself, and why his promises, having an oath annexed to them, ought to be believed. Men when they swear, they swear by the greater; not by themselves, as God does, because there is one greater than they; not by any of the creatures on earth, nor by the angels in heaven, but by God; because he is the God of truth, the searcher of hearts, and who can take vengeance on perjurers: and an oath may lawfully be taken, when it is truth that is sworn to, and is just and good; and in cases of weight and moment; and in what is possible and right to perform; and when it is done with deliberation, in the fear of God, with a view to his glory, and the good of men: for an oath is of a moral nature, what God has commanded, and he himself has taken; it has been used by Christ, and by the saints of the Old and New Testament; and is prophesied of the New Testament saints, as what they should practise; and is a part of religious worship:
and an oath for confirmation is to them an end of all strife; it is used to confirm things that are doubtful, and in dispute; and to put an end to strife and contention; so Philo (o) the Jew says,
"by an oath things doubtful are determined, and things uncertain are confirmed, and what were not believed receive credit.''
The manner in which an oath was taken among the Jews, to which, the apostle writing to such, must be thought to have respect, was this;
"he that swore took the book of the law in his hand, and he stood and swore by the name (of God), or by his surnames; and the judges did not suffer anyone to swear but in the holy tongue; and thus he said, behold I swear by the God of Israel, by him whose name is merciful and gracious, that I do not owe this man anything (p).''
The Hebrew word used for an oath, is of the root which signifies to "fill, satiate, satisfy": for an oath being taken about matters in controversy, not clear but doubtful give content unto and satisfy the minds of men; and the same word also signifies "seven", a number of fulness and perfection; an oath being for the perfecting and finishing an affair in debate; agreeably, when covenants were made by oaths, seven witnesses were used, Genesis 21:28 and Herodotus says (q) as Cocceius (r) observes, that the Arabians, when they swore at making covenants, anointed the stones with blood.
(o) De Somniis, p. 567. (p) Moses Kotsensis Mitzvot Torah, pr. Affirm. 123. (q) Thalia, l. 3. c. 8. (r) Lexic. Rad. col. 848.

for confirmation--not to be joined, as English Version, to "an oath"; but to "an end" [ALFORD]. I prefer, "The oath is to them, in respect to confirmation (of one's solemn promise or covenant; as here, God's), an end of all contradiction (so the Greek is translated, Hebrews 12:3), or "gainsaying." This passage shows: (1) an oath is sanctioned even in the Christian dispensation as lawful; (2) that the limits to its use are, that it only be employed where it can put an end to contradiction in disputes, and for confirmation of a solemn promise.

Men generally swear by him who is infinitely greater than themselves, and an oath for confirmation, to confirm what is promised or asserted, usually puts an end to all contradiction. This shows that an oath taken in a religious manner is lawful even under the gospel: otherwise the apostle would never have mentioned it with so much honour, as a proper means to confirm the truth