For thus saith the LORD of hosts; As I thought to punish you, when your fathers provoked me to wrath, saith the LORD of hosts, and I repented not:
As I thought - I determined.
To punish you - i:e., your fathers, with whom ye are one; the Jewish Church of all ages being regarded as an organic whole (cf. Haggai 2:5; Matthew 23:31-32).
When your fathers provoked me ... and I repented not - I changed not my purpose because they changed not their mind (2 Chronicles 36:16). With the froward, God shows Himself froward (Psalms 18:26). If the threatened punishment has been so unchangeably inflicted, much more will God surely give the promised blessing, which is so much more consonant to His nature (Jeremiah 31:28).