Take ye heed... — The extreme bitterness of the prophet’s words is explained in part by what we read afterwards of his personal history (Jeremiah 12:6; Jeremiah 18:18). Then, as at other times, a man’s foes were those of his own household (Matthew 10:36).
Every brother will utterly supplant. — The word is that which gave the patriarch his significant name of Jacob, the supplanter (Genesis 25:26; Genesis 27:36). Jeremiah seems to say that the people have forfeited their claims to the name of the true Israel. Every brother Israelite is found to be a thorough-paced Jacob. The adverb “utterly” expresses the force of the Hebrew reduplication of the verb.
Will walk with slanders. — Better, walketh a slanderer.