Pharaoh’s army had marched out of Egypt, and when the Babylonians who were besieging Jerusalem heard the report about them, they withdrew from Jerusalem.
References for Jeremiah 37:5
Then the word of the LORD came to Jeremiah the prophet:
“This is what the LORD, the God of Israel, says: Tell the king of Judah, who sent you to inquire of me, ‘Pharaoh’s army, which has marched out to support you, will go back to its own land, to Egypt.
References for Jeremiah 37:7