Leviticus 14:49-53

To cleanse the house then, he shall take two birds and cedar wood and a scarlet string and hyssop, and he shall slaughter the one bird in an earthenware vessel over running water. Then he shall take the cedar wood and the hyssop and the scarlet string, with the live bird, and dip them in the blood of the slain bird as well as in the running water, and sprinkle the house seven times. He shall thus cleanse the house with the blood of the bird and with the running water, along with the live bird and with the cedar wood and with the hyssop and with the scarlet string. However, he shall let the live bird go free outside the city into the open field. So he shall make atonement for the house, and it will be clean.”