Jeremiah 39:3
And all the princes of the king of Babylon came in, and sat in the middle gate, even Nergal-sharezer, Samgar-nebo, Sarsechim, Rab-saris, Nergal-sharezer, Rab-mag, with all the residue of the princes of the king of Babylon. And all the princes of the king of Babylon came in, and sat in the middle gate, even Nergal-sharezer, Samgar-nebo, Sarsechim, Rab-saris, Nergal-sharezer, Rab-mag, with all the residue of the princes of the king of Babylon.
The verse lists the princes of the king of Babylon who entered Jerusalem and seated themselves in the Middle Gate at the taking of the city, in the account of Zedekiah's capture by the Chaldeans. It belongs to the historical portion of Jeremiah treating the events of the two years before Jerusalem fell. It stands in Jeremiah 39:1-14, which in chronological order comes after Jeremiah 39:15-18 though placed first in the chapter, and like other prophecies after chapter 20 it is displaced in order, yet the displacement changes nothing in teaching and the chapter itself makes its chronology clear.
The title Rab-mag borne by one of the princes means chief magician, or chief of the magicians. The verse therefore shows a chief magician among the Babylonian princes present at the capture of Jerusalem, evidencing that the magi at times accompanied the king even in war as his advisers. Rab-mag was the head of the magi, a highly educated priestly class who stood between the Babylonian ruler and the people as his advisers.
The chapter belongs to the account of Jerusalem's fall after Zedekiah refused the Lord's final offer to spare the city if he surrendered to Babylon, teaching the need to heed prophetic counsel and the consequences of refusing it. Zedekiah's sad fate in Jeremiah 39:1-8 came from failing to heed God's word, for though assured that those who surrendered to Babylon would be spared, he feared the people more than he trusted God.