Albert Barnes Commentary Jeremiah 33:2

"Thus saith Jehovah that doeth it, Jehovah that formeth it to establish it; Jehovah is his name:" — Jeremiah 33:2 (ASV)

Or, Thus says Yahweh the doer of it, Yahweh who forms it, that He may establish it, Yahweh is His name. The word “it” means whatever Yahweh wills.