Deuteronomy 24:7

If a man be found stealing (a soul) any of his brethren... — See Exodus 21:16.

(8,9) Take heed in the plague of leprosy.... Remember what the Lord thy God did to Miriam. — The point here seems to be that though Miriam was one of the three leaders of Israel (“I sent before thee Moses, Aaron, and Miriam” — Micah 6:4), yet she was shut out of the camp seven days (Numbers 12:14) when suddenly smitten with leprosy. There might be a tendency to relax the law in the case of great or wealthy persons. But this would be felt keenly by poorer lepers, who could obtain no exemption. Moses, whose own sister had suffered from the leprosy, and had been treated according to the strict letter of the law, would never consent to any relaxation of it.

The priests the Levites. — The law of leprosy was one of the laws which the “priests” in particular were ordered to administer. “Aaron looked on Miriam, and, behold, she was leprous” It seems impossible to maintain that the Levites in general are meant here. The writer evidently had personal knowledge of the case of Miriam. Had he or his first readers lived in later times, he would have explained his meaning more fully.