Jamieson, Fausset and Brown on Jeremiah 21:2

2. Nebuchadrezzar--the more usual way of spelling the name in Jeremiah than Nebuchadnezzar. From Persiac roots, meaning either "Nebo, the chief of the gods," or, "Nebo, the god of fire." He was son of Nabopolassar, who committed the command of the army against Egypt, at Carchemish, and against Judea, to the crown prince.

according to all his wondrous works--Zedekiah hopes for God's special interposition, such as was vouchsafed to Hezekiah against Sennacherib (2Ki 19:35, 36).

he--Nebuchadnezzar.

go up from us--rise up from the siege which he sat down to lay (Jr 37:5, 11, Margin; Nu 16:24, 27; 1Ki 15:19, Margin).