Numbers 31:23-25

Authorized (King James) Version

²³ every thing that may abide the fire, ye shall make it go through the fire, and it shall be clean: nevertheless it shall be purified with the water of separation: and all that abideth not the fire ye shall make go through the water. ²⁴ And ye shall wash your clothes on the seventh day, and ye shall be clean, and afterward ye shall come into the camp.

²⁵ And the Lord spake unto Moses, saying,