Leviticus 14:7, 16, 51

He shall then sprinkle seven times the one who is to be cleansed from the leprosy and shall pronounce him clean, and shall let the live bird go free over the open field.

the priest shall then dip his right-hand finger into the oil that is in his left palm, and with his finger sprinkle some of the oil seven times before the LORD.

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.