'Seventh Day' in the Bible

On the seventh day of the fifth month, which was the nineteenth year of Nebuchadnezzar king of Babylon, Nebuzaradan, the commander of the guards, a servant of the king of Babylon, entered Jerusalem.

On the twenty-seventh day of the twelfth month of the thirty-seventh year of the exile of Judah’s King Jehoiachin, in the year Evil-merodach became king of Babylon, he pardoned King Jehoiachin of Judah and released him from prison.