Lev Leviticus, chapter Book of Leviticus, chapter 10
Aaron's sons, Nadab and Abihu, set light to their incense burners using ordinary fire10:1. “Using ordinary fire”: supplied for clarity. and put in incense, and in this way offered forbidden10:1. “Forbidden”: the words used here means “strange” or “alien.” Clearly the issue was acting in disobedience to God's explicit commands regarding the way in which such items were to be used in his service. The fire was to come from the altar. fire in the Lord's presence, something he had not authorized. Num 3:4; 1Ch 24:2