'Swore' in the Bible

Then King Zedekiah, in secret, swore an oath to Jeremiah: "As surely as the LORD lives, who gave us this life to live, I won't have you put to death, nor will I hand you over to these men who are seeking to kill you."

Ahikam's son Gedaliah, the grandson of Shaphan, swore an oath to them and their men: "Don't be afraid to serve the Chaldeans. Remain in the land and serve the king of Babylon, and things will go well for you.