Leviticus 16:12-13

ISV(i) 12 Then he is to take a censer and fill it with coals from the fire on the altar in the LORD’s presence. With his hands full of spiced and refined incense, he is to bring it beyond the curtain.
13 “Then he is to place the incense over the fire in the LORD’s presence, ensuring that the smoke from the incense covers the Mercy Seat, according to regulation, so he won’t die.