Deuteronomy 29:18-21 Lest there should be among you man, or woman, or family, or tribe, whose heart turneth away this day from the LORD our God, to go and serve the gods of these nations; lest there should be among you a root that beareth gall and wormwood; and it come to pass, when he heareth the words of this curse, that he bless himself in his heart, saying, "I shall have peace, though I walk in the imagination of mine heart, to add drunkenness to thirst." 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. And the LORD shall separate him unto evil out of all the tribes of Israel, according to all the curses of the covenant that are written in this book of the law.
The Abuser Described — Deuteronomy 29:18
He is 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 tempted when they are drawn aside by their own lusts and fancies. Those that begin to turn from God, by neglecting their duty to Him, are easily drawn to other gods; and those that serve other gods do certainly turn away from the true God, for He will admit of no rivals. God will be all or nothing.
Philippians 3:18-10 Many walk, of whom I have told you often, and now tell you even weeping, that they are the enemies of the cross of Christ: whose end is destruction, whose god is their belly, and whose glory is in their shame, who mind earthly things.
He is a root that bears gall and wormwood; that is, he is a dangerous man, who, being himself poisoned with bad principles and inclinations—with a secret contempt of the God of Israel and His institutions and with a veneration for the gods of the nations—endeavors, by all possible craftiness, to corrupt and poison others and draw them to idolatry. This is a man whose fruit is hemlock (so the word is translated in Hosea 10:4) and wormwood; it is very displeasing to God, and will be bitterness in the latter end to all that are seduced by him. This is referred to by the apostle in Hebrews 12:15, where he is in like manner cautioning us to take heed of those that would seduce us from the Christian faith. They are the weeds or tares in a field, which, if let alone, will overspread the whole field. A little of this leaven will be in danger of infecting the whole lump.
Their Security in Sin and Idolatry — Deuteronomy 29:19
He promises himself impunity, though he persists in his impiety. Though he hears the words of the curse, so that he cannot, as other idolaters, plead ignorance of the danger, yet even then he blesses himself in his own heart, thinks himself safe from the wrath of the God of Israel, under the protection of his idols, and therefore says, "I shall have peace, though I be governed in my religion, not by God's institution, but by my own imagination, to add drunkenness to thirst—one act of wickedness to another."
Idolaters were like drunkards, violently set upon their idols themselves and industrious to draw others in with them. Revellings commonly accompanied their idolatries (1 Peter 4:3), so that this speaks a woe to drunkards who, when they are awake, being thirsty, seek it yet again (Proverbs 23:35). And those that made themselves drunk in honor of their idols were the worst of drunkards.
We must note 3 things concerning this ensnaring sin of idolatry:
There are many who are under the curse of God and yet bless themselves; but it will soon be found that in blessing themselves they only deceive themselves.
Those are ripe for ruin, and there is little hope of their repentance, who have made themselves believe that they shall have peace even though they go on in a sinful way.
Drunkenness is a sin that hardens the heart and debauches the conscience, as much as any other, a sin to which men are strangely tempted themselves even when they have lately felt the mischiefs of it, and to which they are strangely fond of drawing others (Habakkuk 2:15).
God's Just Severity Against Them — Deuteronomy 29:20-21
God is just in His expressed severity against them for both the sin and the impious affront they put upon Him in saying they should have peace even though they went on, and thereby giving the lie to eternal truth (Genesis 3:4). There is scarcely a threatening in all the book of God that sounds more dreadful than this. O that presumptuous sinners would read it and tremble! For it is not a bugbear to frighten children and fools, but a real declaration of the wrath of God against the ungodliness and the unrighteousness of men.
The Lord shall not spare him. The days of his reprieve, which he abuses, will be shortened, and no mercy remembered in the midst of judgment.
The anger of the Lord, and His jealousy—which is the fiercest anger—shall burn against him like the smoke of a furnace.
The curses written shall lie upon him, not only to terrify him, but abide upon him—to sink him to the lowest hell (John 3:36).
His name shall be blotted out, that is, he himself shall be cut off, and his memory shall rot and perish with him.
He shall be singled out for adversity—which is the most proper notion of a curse; he shall be cut off from all happiness and all hope of it, and marked out for misery without remedy.
All this according to the curses of the covenant—which are the most fearful curses, being the just revenges of abused grace.
1 Thessalonians 5:3 For when they shall say, "Peace and safety!" then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape.
Hebrews 3:12-14 Take heed, brethren, lest there be in any of you an evil heart of unbelief, in departing from the living God. But exhort one another daily, while it is called "Today," lest any of you be hardened through the deceitfulness of sin. For we are made partakers of Christ, if we hold the beginning of our confidence stedfast unto the end…
Adapted and slightly edited from Matthew Henry's Commentary on Deuteronomy 29:10-29.