Then the Lord will not spare him,.... Have no mercy upon him, nor forgive him, being an hardhearted, impenitent, stubborn, and obstinate sinner, as well as guilty of the grossest and most provoking sin, as idolatry is:

but then the anger of the Lord, and his jealousy, shall smoke against that man; or, "the nose of the Lord shall smoke" (f); alluding to an angry, wrathful, furious man, whose brain being heated, and his passions inflamed, his breath steams through his nostrils like smoke; it denotes the vehement anger, the greatness of God's wrath and indignation against such a person, and his burning zeal or jealousy for his own honour and glory injured by the idolater:

and all the curses that are written in this book shall lie upon him: for as he that offends in one point is guilty of all, and especially in such a principal point as this, which concerns the being and worship of God; so he makes himself liable to all the curses of the law, which shall not only come upon him, but abide on him; and there is no person clear of them but by redemption through Christ, who, by being made a curse for his people, has redeemed them from the curse of the law:

and the Lord shall blot out his name from under heaven; he shall have no name in Israel, not in the church, and among the people of God, from whom he is to be excommunicated; shall have no name and place in the earth, being cut off from the land of the living; and shall have no name or fame after his death, his memory shall rot and perish; and he shall appear to have no name in the book of life; see Psalm 69:28.

(f) "fumabit nasus Domini", Montanus.

"For the Lord will not forgive him (who thinks or speaks in this way); but then will His anger smoke (break forth in fire; vid., (Psalm 74:1), and His jealousy against that man, and the whole curse of the law will lie upon him, that his name may be blotted out under heaven (vid., Deuteronomy 25:19; Exodus 17:14). "The Lord will separate him unto evil from all the tribes, - so that he will be shut out from the covenant nation, and from its salvation, and be exposed to destruction - according to all the curses of the covenant." Although the pronominal suffix refers primarily to the man, it also applies, according to Deuteronomy 29:18, to the woman, the family, and the tribe. "That is written," etc., as in Deuteronomy 28:58, Deuteronomy 28:61.

The LORD will not spare him, but then the anger of the LORD and his jealousy shall smoke against that man, and all the curses that are written in this book shall lie upon him, and the LORD shall blot out his name from under heaven.

29:20 Shall smoke - Shall burn and break forth with flame and smoke as it were from a furnace.

29:10-21 The national covenant made with Israel, not only typified the covenant of grace made with true believers, but also represented the outward dispensation of the gospel. Those who have been enabled to consent to the Lord's new covenant of mercy and grace in Jesus Christ, and to give up themselves to be his people, should embrace every opportunity of renewing their open profession of relation to him, and their obligation to him, as the God of salvation, walking according thereto. The sinner is described as one whose heart turns away from his God; there the mischief begins, in the evil heart of unbelief, which inclines men to depart from the living God to dead idols. Even to this sin men are now tempted, when drawn aside by their own lusts and fancies. Such men are roots that bear gall and wormwood. They are weeds which, if let alone, overspread the whole field. Satan may for a time disguise this bitter morsel, so that thou shalt not have the natural taste of it, but at the last day, if not before, the true taste shall be discerned. Notice the sinner's security in sin. Though he hears the words of the curse, yet even then he thinks himself safe from the wrath of God. There is scarcely a threatening in all the book of God more dreadful than this. Oh that presumptuous sinners would read it, and tremble! for it is a real declaration of the wrath of God, against ungodliness and unrighteousness of man.