'Seventh Day' in the Bible

On the seventh day of the fifth month, which was during the nineteenth year of King Nebuchadnezzar's reign as king of Babylon, captain of the guard Nebuzaradan, a servant of the king of Babylon, arrived in Jerusalem

Later on, after King Jehoiachin of Judah had been in exile for 37 years, on the twenty-seventh day of the twelfth month, during the first year of his reign, King Evil-merodach of Babylon released King Jehoiachin of Judah from prison.