Jealousy is the rage of a man: therefore he will not spare - He will not, when he has detected the adulterer in the fact, wait for the slow progress of the law: it is then to him the day of vengeance; and in general, he avenges himself on the spot, as we see above.

For jealousy [is] the rage of a man: therefore he will not (r) spare in the day of vengeance.
(r) He shows that man by nature seeks the death of he that has abused his wife, and so concludes that neither God's law nor the law of nature admits any ransom for the adultery.

For jealousy is the rage of a man,.... Fills a man with rage against him of whom he is jealous; which keeps boiling within him, till he has an opportunity of venting it: and very severe it is; it is strong as death, and cruel as the grave;
therefore he will not spare in the day of vengeance; when he has an opportunity of avenging himself; whenever he finds the adulterer in his house, or catches him and his wife in bed together, he spares not to take away his life, and sometimes the life of both of them; instances of this nature history furnishes us with: or he will spare no cost and pains to prosecute him before a civil magistrate, and bring him to public justice; prayers and entreaties, bribes and gifts, wilt be of no avail, as follows.

nor any terms of reconciliation be admitted.
regard--or, "accept" any ransom.

One who has been stolen from is to be appeased, but not the injured husband.
34 For jealousy is the fury of a husband,
And he spareth not in the day of vengeance.
35 He regardeth not any ransom,
And is not contented though thou offerest to him gifts ever so great.
The connection marks קנאה as the subject; for it respects carnal intercourse with another's wife. Jealousy is not usually חמה, the glow of anger (from יחם, as שׁנה from ישׁן), but חמת־גּבר (constr. as שׂנת), the glow of a man's anger, who with the putting forth of all his manly strength will seek satisfaction to his wounded honour. גּבר, here significant for אישׁ, with the fundamental idea of strength, firmness; cf. Arab. jabr, to make fast, to put right again something broken in pieces, particularly a broken vessel, hence Algebra, properly the operation by which an incomplete magnitude is completed (Fl.). The following ולא־יחמּל (with the orthophonic Dagesh, as Proverbs 6:25 יחמּד, and with Makkeph) is connected with גבר, with definite reference to the man whom the faithless guest has made a cuckold. When the day comes in which the adultery brought to light demands and admits of vengeance, then, wounded in his right and in his honour, he knows no mercy; he pays no regard to any atonement or recompense by which the adulterer seeks to appease him and induce him not to inflict the punishment that is due: he does not consent, even though thou makest ever so great the gift whereby thou thinkest to gain him. The phrase נשׂא פנים, πρόσωπον λαμβάνειν, signifies elsewhere to receive the countenance, i.e., the appearance and the impression of a man, i.e., to let it impress one favourably; here it is used of the כּפר, i.e., the means by which covering, i.e., non-punishment, pardon of the crime, impunity of the guilty, is obtained. Regarding אבה, to consent to, vid., at Proverbs 1:10. שׂחד, Aram. שׂוּחד, is a gift, particularly bribery. That the language may again finally assume the form of an address, it beautifully rounds itself off.

Rage - It enflames a man with rage. In the day - When he hath an opportunity to avenge himself.