Charles Ellicott Commentary Jeremiah 38:16

"So Zedekiah the king sware secretly unto Jeremiah, saying, As Jehovah liveth, that made us this soul, I will not put thee to death, neither will I give thee into the hand of these men that seek thy life." — Jeremiah 38:16 (ASV)

As the Lord liveth, that made us this soul. —The formula of the oath was obviously intended to be one of unusual solemnity; even more so than the simpler form of The Lord liveth (Jeremiah 16:14–15). The king swears by Jehovah as the living God, author and giver of his own life. The twofold promise shows that the king felt the implied reproof of Jeremiah’s question. He separates himself from those who sought the prophet’s life and declares that in the future he will not give them even the sanction of acquiescence. It is characteristic of his weakness that even now the oath is given secretly.