Jeremiah 37:5

Then Pharaoh's army was come forth out of Egypt,.... At the time the above message was sent to Jeremiah. Zedekiah, though he had took an oath of homage to the king of Babylon, rebelled against him, and entered into a league with the king of Egypt, to whom he sent for succours in his distress; and who, according to agreement, sent his army out of Egypt to break up the siege of Jerusalem; for though the king of Egypt came no more in person out of his land, after his defeat at Carchemish by Nebuchadnezzar, in the fourth year of Jehoiakim,

Jeremiah 46:2; yet he sent his army to the relief of Jerusalem:

and when the Chaldeans that besieged Jerusalem; which was in the ninth year of Zedekiah's reign that they first besieged it, and is the time here referred to, Jeremiah 39:1;

heard tidings of them; the Egyptian army, and of its coming out against them; the rumour of which might be spread by the Jews themselves, to intimidate them; or which might come to them by spies they had in all parts to give them intelligence of what was doing; and what they had was good and certain, and on which they acted:

they departed from Jerusalem: not through fear, but to meet the Egyptian army, and give them battle, before they could be joined by any considerable force of the Jews. It was at this time the covenant was broken about the manumission of servants, Jeremiah 34:10; which conduct ill agrees with their desire of the prophet's prayer.