Deuteronomy 33:8-10

And of Levi he said, Thy Thummim and thy Urim are with thy godly one, Whom thou didst prove at Massah, With whom thou didst strive at the waters of Meribah; Who said of his father, and of his mother, I have not seen him; Neither did he acknowledge his brethren, Nor knew he his own children: For they have observed thy word, And keep thy covenant. They shall teach Jacob thine ordinances, And Israel thy law: They shall put incense before thee, And whole burnt-offering upon thine altar.