Leviticus 9:24-10:11
Fire came forth from before the Lord and consumed the burnt offering and the fat parts on the altar. And all the people saw, and shouted, and fell on their faces.
Now Aaron's sons Nadab and Abihu each took his fire pan, put fire in it, and laid incense on it; and they offered before the Lord alien fire, which He had not enjoined upon them. And fire came forth from the Lord and consumed them; thus they died at the instance of the Lord. Then Moses said to Aaron, "This is what the Lord meant when He said:
Through those near to Me I show Myself holy,
And gain glory before all the people."
And Aaron was silent.
Moses called Mishael and Elzaphan, sons of Uzziel the uncle of Aaron, and said to them, "Come forward and carry your kinsmen away from the front of the sanctuary to a place outside the camp." They came forward and carried them out of the camp by their tunics, as Moses had ordered. And Moses said to Aaron and to his sons Eleazar and Ithamar, "Do not bare your heads and do not rend your clothes, lest you die and anger strike the whole community. But your kinsmen, all the house of Israel, shall bewail the burning that the Lord has wrought. And so do not go outside the entrance of the Tent of Meeting, lest you die, for the Lord's anointing oil is upon you." And they did as Moses had bidden.
And the Lord spoke to Aaron, saying: Drink no wine or other intoxicant, you or your sons, when you enter the Tent of Meeting, that you may not die. This is a law for all time throughout the ages, for you must distinguish between the sacred and the profane, and between the unclean and the clean; and you must teach the Israelites all the laws which the Lord has imparted to them through Moses.