From the iron furnace - Rather, out of “the iron furnace,” Egypt (see Deuteronomy 4:20). The constant reference to Deuteronomy shows how great had been the effect upon Jeremiah’s mind of the public recitation of the “Book of the covenant” found in the temple.
Related Commentaries of Jeremiah 11:4
Jeremiah 11:4
4 Which I commanded your fathers in the day that I brought them forth out of the land of Egypt, from the iron furnace, saying, Obey my voice, and do them, according to all which I command you: so shall ye be my people, and I will be your God: