yasyāṁ janma vidur hareḥ

dvadasyam-on the twelfth day of the moon; savita-the sun; atisthat-was staying; madhyam-dina-gatah-on the meridian; nrpa-O King; vijaya-nama-by the name Vijaya; sa-that day; prokta-is called; yasyam-on which; janma-the appearance; viduh-they know; hareh-of Lord Hari.