'Twelfth' in the Bible

Now it came about in the thirty-seventh year of the exile of Jehoiachin [also called Coniah and Jeconiah] king of Judah, in the twelfth month, on the twenty-fifth of the month, Evil-merodach king of Babylon, in the first year of his reign, showed favor to Jehoiachin king of Judah and brought him out of prison.