Charles Ellicott Commentary Lamentations 3:65

"Thou wilt give them hardness of heart, thy curse unto them." — Lamentations 3:65 (ASV)

Sorrow of heart —Literally, covering, with a sense like that of the “veil upon the heart” of 2 Corinthians 3:15, and so signifying the blindness of obstinacy. The imperatives in both Lamentations 3:65-66 are better rendered as futures— You shall give; You shall persecute.