As I thought to punish you - (Literally, to do evil to you) “and repented not.” In like way God says in Jeremiah, “I have purposed and will not repent.” Jeremiah 4:28.
Matthew Henry
Concise Bible Commentary
Those only who lay their hands to the plough of duty, shall have them strengthened with the promises of mercy: those who avoid their fathers' faults have the curse turned into a blessing. Those who believed the promises, were to show their faith by their works, and to wait the fulfilment. When God is displeased, he can cause trade to decay, and set every man against his neighbour; but when he returns in mercy, all is happy and prosperous. Surely believers in Christ must not trifle with the exhortation to put away lying, and to speak every man peace with his neighbour, to hate what the Lord hates, and to love that wherein he delights.