22 Only the gold, and the silver, the copper, the iron, the tin, and the lead, 23 everything that passeth through the fire, ye shall make it go through the fire, and it shall be clean; only it shall be purified with the water of separation; and everything that cannot pass through the fire ye shall make go through the water. 24 And ye shall wash your garments on the seventh day, and ye shall be clean; and afterwards ye may come into the camp.

Matthew Henry's Commentary on Numbers 31:22-24

Commentary on Numbers 31:19-24

(Read Numbers 31:19-24)

The Israelites had to purify themselves according to the law, and to abide without the camp seven days, though they had not contracted any moral guilt, the war being just and lawful, and commanded by God. Thus God would preserve in their minds a dread and detestation of shedding blood. The spoil had been used by Midianites, and being now come into the possession of Israelites, it was fit that it should be purified.