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 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 .'
'The Hebrew word hebv, used for an oath, is of the root ebv, 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, Ge 21:28 and Herodotus says as Cocceius observes, that the Arabians, when they swore at making covenants, anointed the stones with blood.
De Somniis, p. 567. Moses Kotsensis Mitzvot Torah, pr. Affirm. 123. Thalia, l. 3. c. 8. Lexic. Rad. ebv col.