Leviticus 14:6-7

6as to the living bird — he shall take it, and the cedar-wood, and the scarlet, and the hyssop, and dip them and the living bird in the blood of the bird that was killed over the running water;

7and he shall sprinkle upon him that is to be cleansed from the leprosy seven times, and shall pronounce him clean, and shall let the living bird loose into the open field.