Albert Barnes Commentary Lamentations 2:17

"Jehovah hath done that which he purposed; he hath fulfilled his word that he commanded in the days of old; He hath thrown down, and hath not pitied: And he hath caused the enemy to rejoice over thee; he hath exalted the horn of thine adversaries." — Lamentations 2:17 (ASV)

What he had devised - Or, what he purposed. Zion’s ruin was the fulfillment of God’s determination, of which they had been forewarned from the days of old (see the margin reference).

Fulfilled - Or, finished.