Charles Ellicott Commentary Jeremiah 37:5

"And Pharaoh`s army was come forth out of Egypt; and when the Chaldeans that were besieging Jerusalem heard tidings of them, they brake up from Jerusalem." — Jeremiah 37:5 (ASV)

Then Pharaoh’s army was come forth out of Egypt. —The dispatch of the Egyptian army was the result of negotiations which Zedekiah had opened with Pharaoh-Hophra, with a view to resisting the power of Nebuchadnezzar (Ezekiel 17:15). Like the Egyptian armies in general, it was strong in chariots and horses (Ezekiel 17:15; Isaiah 31:1; Isaiah 36:9), and able to carry out the operations of a siege (Ezekiel 17:17). In Jeremiah 44:30 we have the full name of the Egyptian king.