Leviticus 14:49-53

To purify the house the priest must take two birds, a stick of cedar, some scarlet yarn, and a hyssop branch. He will slaughter one of the birds over a clay pot filled with fresh water. He will take the cedar stick, the hyssop branch, the scarlet yarn, and the live bird, and dip them into the blood of the slaughtered bird and into the fresh water. Then he will sprinkle the house seven times. When the priest has purified the house in exactly this way, he will release the live bird in the open fields outside the town. Through this process, the priest will purify the house, and it will be ceremonially clean.