John Gill Commentary Zechariah 8:14

"For thus saith Jehovah of hosts: As I thought to do evil unto you, when your fathers provoked me to wrath, saith Jehovah of hosts, and I repented not;" — Zechariah 8:14 (ASV)

For thus says the Lord of hosts In order to assure them of the truth of what he promised, he observes the fulfilment of what he has threatened, he being as true and faithful in the one as in the other.

As I thought to punish you: determined to do it, by suffering them to be carried captive.

when your fathers provoked me to wrath, says the Lord of hosts; by their immorality, idolatry, and contempt of his prophets.

and I repented not; the Targum adds, "of my word"; of the resolution he had taken up in his heart, and of the declaration of it by his prophets, that he would punish them; this he did not repent of, revoke, change, and alter, but steadily abode by it, and executed it.