Nadav and Avihu

In the biblical books Exodus, Leviticus and Numbers, Nadab (Hebrew: נדב, Nadav; "generous, giving") and Abihu (Hebrew: אביהוא, Avihu; "he is my father") were the two eldest sons of Aaron. According to Leviticus 10, they offered a sacrifice with 'strange fire' before the LORD, disobeying his instructions, and were immediately consumed by God’s fire.

Moses instructed Aaron and his family not to mourn, although the people at large were permitted.

Nadab and Abihu were the first two sons of Aaron the Levite by his marriage to Elisheba, daughter of Amminadab from the tribe of Judah. They had four sons in total, the younger two sons being named Eleazar and Ithamar. During the Exodus journey, after the Israelites' affirmation of their covenant with God, Abihu and Nadab accompanied Moses, Aaron, and 70 elders up Mount Sinai. There they 'saw' God with great clarity, walking on a pavement of sapphire stone, and shared a meal in God's presence, without being harmed as a result.

Aaron and his four sons were the first priests appointed as the priestly system was established by God. The Levites as a tribe were later ordained for the priestly service after answering a call to take the LORD’s side after the idolatry centered around the golden calf. After the death of Nadab and Abihu, Eleazar and Ithamar took their places as priests, because neither Nadab nor Abihu had any sons.

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