'Seventh Day' in the Bible

On the seventh day of the fifth month, in the nineteenth year of King Nebuchadnezzar of Babylon, Nebuzaradan, the captain of the royal guard who served the king of Babylon, arrived in Jerusalem.

In the thirty-seventh year of the exile of King Jehoiachin of Judah, on the twenty-seventh day of the twelfth month, King Evil-Merodach of Babylon, in the first year of his reign, pardoned King Jehoiachin of Judah and released him from prison.