Jeremiah 15:12 - Coke's Commentary on the Holy Bible

Shall iron break the northern iron— Houbigant renders the verse, I will raise up iron from the north, iron and brass; which seems to give the best interpretation of this difficult verse. Others understand it in a different manner, thus: The Lord, to comfort Jeremiah, promises him in the 11th verse, that he will cause his enemies at the end to treat him well: but he adds in this verse, "What do you fear from the Jews? What can they do against you? Though they were as hard as iron or as steel, they cannot hurt you. I will give you the solidity of brass, the force of northern iron: thou shalt be as a brazen wall, against which all their attacks shall be in vain." See Jeremiah 15:20 and ch. Jeremiah 1:17-18.