Charles Ellicott Commentary Isaiah 34:8

"For Jehovah hath a day of vengeance, a year of recompense for the cause of Zion." — Isaiah 34:8 (ASV)

The year of recompences for the controversy of Zion ... —The long-delayed day of retribution should come at last. This would be the outcome from the hand of Jehovah for the persistent hostility of the Edomites to the city which He had chosen.