Leviticus 16:11-14

When Aaron sacrifices the bull as the sin offering for himself and his family, he shall take a firepan full of burning coals from the altar and two handfuls of fine incense and bring them into the Most Holy Place. There in the LORD's presence he shall put the incense on the fire, and the smoke of the incense will hide the lid of the Covenant Box so that he will not see it and die. He shall take some of the bull's blood and with his finger sprinkle it on the front of the lid and then sprinkle some of it seven times in front of the Covenant Box.