Aaron is the brother of *Moses and *Miriam; he speaks for Moses and performs signs on his behalf before the Exodus from *Egypt (Exod 4:10–17, 27–31; 7:19; 8:1; 8:12). Aaron is also the father of the levitical *priesthood (Exod 28:1); Leviticus 8–10 describes the ordination of Aaron and his sons as the priests (kohanim) of the *Tabernacle. Nadab and Abihu, two of Aaron's sons, die in the course of this event (Lev 10:1–3), apparently because they disobey God by incorporating foreign elements into the cultic service. Numbers 18 affirms the primacy of the priestly roles of Aaron and his direct descendants: They alone are responsible for maintaining the purity of the sanctuary (18:1), while the other members of the tribe of Levi are to provide support services and “do the work of the Tent of Meeting” (Num 18:2–7). Aaron sometimes challenges his brother's leadership. When Moses ascends Mount Sinai, Aaron stays behind and is persuaded to build the golden calf; he is spared, however, from the plague that strikes the idolaters (Exod 32). Numbers 12 relates that both Aaron and Miriam speak against Moses and challenge the unique nature of Moses’ prophetic relationship with God. Both are verbally chastised by God, but only Miriam is punished with a skin affliction and a week's expulsion from the camp. Aaron, like Moses, is barred from entrance to *Canaan for his failure to sanctify God as commanded at the waters of Meribah (Num 20:1–13).