And this shall be a sign unto you, saith the LORD, that I will punish you in this place, that ye may know that my words shall surely stand against you for evil: This shall be a sign unto you - the calamity of Pharaoh-hophra (note, Jeremiah 44:30) shall be a sign to you, that as he shall fall before his enemy, so you shall subsequently fall before Nebuchadnezzar (Matthew 24:8). (Grotius.) Calvin makes the "sign" to be simultaneous with the event signified, not antecedent to it, as in Exodus 3:12. The Jews believed Egypt impregnable, so shut in was it by natural barriers. The Jews being "punished in this place" will he a sign that their view is false, and God's threat true. He calls it "a sign unto you," because God's prediction is equivalent to the event, so that they may even now take it as a sign. When fulfilled it would cease to be a sign to them, for they would be dead.
Related Commentaries of Jeremiah 44:29
Jeremiah 44:29
29 And this shall be a sign unto you, saith the LORD, that I will punish you in this place, that ye may know that my words shall surely stand against you for evil: