Therefore saith the Lord, the LORD of hosts, the mighty One of Israel, Ah, I will ease me of mine adversaries, and avenge me of mine enemies:
Therefore saith the Lord, the Lord of hosts - 'Adonaay (H136), Yahweh (H3068).
The mighty One of Israel - mighty to take vengeance, as before to save.
Ah - Indignation.
I will ease me of mine adversaries - my long-tried patience will find relief in at last punishing the guilty (Ezekiel 5:13). God's language condescends to human conceptions.