Abihu, Son of Aaron (אֲבִיהוּא, avihu'). Second son of Aaron. He and his older brother Nadab died before Yahweh when the two presented “illegitimate fire, which he had not commanded them” (Lev 10:1–2).

There are at least three possible explanations for why they died. First, it is possible that their fault was presumption. They offered incense on their own initiative, rather than waiting for Yahweh’s command. Second, they may have taken coals from an unauthorized or ritually impure source; Leviticus 16:12 requires Aaron to fill his censer with coals from the altar. Third, in light of the fact that Yahweh’s next command—six verses later—is a prohibition of drinking alcohol before entering the Tent of Meeting (Lev 10:9), it is possible that Nadab and Abihu were intoxicated when they offered the incense.

Their deaths are mentioned three times later in the Old Testament (Num 3:4; 26:61; 1 Chr 24:2). The text emphasizes that they had no children, and that no part of Aaron’s priestly line was descended from them (Num 3:4).