Num Numbers, chapter Book of Numbers, chapter 3
But, while Yahweh was watching, Nadab and Abihu died in the Sinai Desert because they burned incense in a manner that was different from what Yahweh had commanded. They had no sons, so Eleazar and Ithamar were the only sons of Aaron who were left to be priests, along with their father Aaron.Lev 10:1; 1Ch 24:2