Jeremiah 37:5
Then Pharaoh’s army was come forth out of Egypt: and when the Chaldeans that besieged Jerusalem heard tidings of them, they departed from Jerusalem. Then Pharaoh’s army was come forth out of Egypt: and when the Chaldeans that besieged Jerusalem heard tidings of them, they departed from Jerusalem.
Egypt's army came forth out of Egypt to bring aid to Jerusalem, and when the Chaldeans who were besieging the city heard of their advance they broke off the siege and withdrew from Jerusalem to turn back that Egyptian force. The lifting of the siege was only temporary, a pause in the pressure upon the city while the Chaldeans moved to confront the new threat. That brief respite revived hope in Zedekiah that Jerusalem might yet be delivered. In that hope he sent to Jeremiah, asking the prophet to pray to God on behalf of the nation.