Leviticus 14:5-7

⁵The priest shall command them to kill one of the birds in an earthen vessel over running water.

⁶As for the living bird, he shall take it, the cedar wood, the scarlet, and the hyssop, and shall dip them and the living bird in the blood of the bird that was killed over the running water.

⁷He shall sprinkle on him who is to be cleansed from the leprosy seven times, and shall pronounce him clean, and shall let the living bird go into the open field.