Numbers 19:5-7

⁵And some one shall burn the cow before his eyes; her skin, and her flesh, and her blood, with her dung, shall he burn.

⁶And the priest shall take cedar-wood, and hyssop, and a scarlet string, and cast it into the midst of the burning of the cow.

⁷And the priest shall wash his clothes, and he shall bathe his flesh in water, and afterward may he come into the camp; and the priest shall be unclean until the evening.