For it is the day of vengeance of Jehovah. This verse must be viewed as closely connected with the preceding verses, for it points out the object which the Lord has in view in punishing the Edomites with such severity; and that object is, that he wishes to avenge his people and defend their cause. If, therefore, he had not also assigned this reason, the former statements might have appeared to be obscure or inappropriate; for it would, have been an uncertain kind of knowledge if we did not consider that God, in punishing wicked men, testifies his unceasing affection and care to preserve his own people. What was formerly said about the Edomites must undoubtedly be extended to the enemies of the Church, for all of them were included by the Prophet under a particular class; and, therefore, in adversity our hearts ought to be supported by this consolation, that the attacks which we now suffer shall come into judgment before God, who justly claims for himself this office. The Prophet does not only mean that it is in his power to punish wicked men whenever he thinks proper, but, that he reigns in heaven, in order to punish every kind of injustice at the proper time. But we must attend to the words day and year, by which he reminds us that God does not sleep in heaven, though for a little time he does not come forth, but delays his vengeance till a fit season, that believers may in the meantime "possess their souls in patience," (Luke 21:19,) and may leave him to govern according to his inscrutable wisdom.

For it is the day of the Lord's vengeance - A time when Yahweh will take vengeance.
The year of recompenses for the controversy of Zion - The time when he will recompense, that is, punish those who have had a controversy with Zion.

The year of recompenses for the controversy of Zion "The year of recompense to the defender of the cause of Zion" - As from דון dun, דין din, a judge; so from רוב rub, ריב rib, an advocate, or defender; Judici Sionis: Syriac.

For it is the day of the Lord's vengeance,.... The time which he has appointed to take vengeance on antichrist, his 1260 days, or years; being up, in which he is to reign; these being expired, the time is come for the Lord to avenge the blood of his saints; see Revelation 18:20,
and the year of recompences for the controversy of Zion; the church of God, which has been for many ages abused and injured by the antichristian powers, for which the Lord will have a controversy with them; he will appear in favour of his people, and plead the cause of Zion, and recompense their enemies for all the injuries they have done them; then they that have led into captivity shall go into captivity, and they that have killed with the sword shall be killed with it, Revelation 13:10 this will be a time of double recompence; and therefore perhaps the word is used in the plural number; it will be the time of rewarding antichrist as he has rewarded others; and it will be the time of the dead, that they shall be judged, and rewards given to God's servants the prophets, Revelation 18:6. The Targum is,
"the year of recompence, to take vengeance of judgment for the injury of Zion.''

recompenses for the controversy of Zion--that is, the year when God will retaliate on those who have contended with Zion. Her controversy is His. Edom had thought to extend its borders by laying hold of its neighbor's lands and has instigated Babylon to cruelty towards fallen Judah (Psalm 137:7; Ezekiel 36:5); therefore Edom shall suffer the same herself (Lamentations 4:21-22). The final winding up of the controversy between God and all enemies of Him and His people is also foreshadowed (Isaiah 61:2; Isaiah 63:4; Isaiah 66:14-16; Malachi 4:1, Malachi 4:3; 2-Thessalonians 1:7-9; Revelation 11:18; Revelation 18:20; Revelation 19:2).

Thus does Jehovah avenge His church upon Edom. "For Jehovah hath a day of vengeance, a year of recompense, to contend for Zion. And the brooks of Edom are turned into pitch, and its dust into brimstone, and its land becomes burning pitch. Day and night it is not quenched; the smoke of Edom goes up for ever: it lies waste from generation to generation; no one passes through it for ever and ever." The one expression, "to contend for Zion," is like a flash of lightning, throwing light upon the obscurity of prophecy, both backwards and forwards. A day and a year of judgment upon Edom (compare Isaiah 61:2; Isaiah 63:4) would do justice to Zion against its accusers and persecutors (rı̄bh, vindicare, as in Isaiah 51:22). The everlasting punishment which would fall upon it is depicted in figures and colours, suggested by the proximity of Edom to the Dead Sea, and the volcanic character of this mountainous country. The unquenchable fire (for which compare Isaiah 66:24), and the eternally ascending smoke (cf., Revelation 19:3), prove that the end of all things is referred to. The prophet meant primarily, no doubt, that the punishment announced would fall upon the land of Edom, and within its geographical boundaries; but this particular punishment represented the punishment of all nations, and all men who were Edomitish in their feelings and conduct towards the congregation of Jehovah.

For - This is the time which God hath fixed, to avenge the cause of his persecuted people.