Deuteronomy 33:8-9

And of Levi he said, {Let} thy Thummim and thy Urim {be} with thy holy one, whom thou didst prove at Massah, {and with} whom thou didst strive at the waters of Meribah; Who said unto his father and to his mother, I have not seen him; neither did he acknowledge his brethren, nor knew his own children: for they have observed thy word, and kept thy covenant.