“And you, draw Aaron your brother near to you, and his sons with him, from among the children of Israel, to serve Me: Aaron, Nadav and Avihu, Elazar and Itamar, Aaron’s sons” (Exodus 28:1). “And you, draw Aaron your brother near to you,” that is what is written: “From it will come a cornerstone, from it a peg, from it a bow of war” (Zechariah 10:4). Come and see: When the early nations would seek to appoint a king for themselves, they would bring [a man] from anywhere and appoint him over them, as it says: “He reigned in Edom” (Genesis 36:32), from Dinhava, from Basra, and likewise, all of them.1The Torah (Genesis 36:32–39) lists various kings of Edom and where they were from; the first two were from Dinhava and Basra, respectively.
These places were not in Edom. But Israel is not so. Their great ones are from them, their kings are from them, their priests are from them, their prophets are from them, their princes are from them, as it is stated: “From it will come a cornerstone,” this is King David, as it is stated: “The stone that the builders rejected became the cornerstone” (Psalms 118:22).2The Sages apply this verse to King David (see Midrash Tehillim 118), who was a humble shepherd and the youngest and least prominent of his brothers before he was appointed king.
“From it a peg” this is the High Priest, as it is stated: “I will affix him as a peg in a secure place” (Isaiah 22:23). “From it a bow of war,” as it is stated: “They were armed with bows, both right and left-handed” (I Chronicles 12:2). “From it every oppressor will be gone together” (Zechariah 10:4), these are the judges’ scribes. And likewise it says: “And you, draw Aaron your brother near to you, and his sons with him.”
From where? It is from among the children of Israel. This is analogous to a king who had a friend and sought to appoint a treasurer, and he appointed [his friend] over his entire treasury. Sometime later, he sought to appoint a military chief of staff, and that friend thought that perhaps he would choose him, but he did not choose him. [The king] said to him: ‘Go and appoint a military chief of staff.’
He said to him: ‘My lord, from which noble family?’ He said to him: ‘From your noble family.’ So too, the Holy One blessed be He sought to appoint someone over the labor of the Tabernacle, and He selected Moses as the administrator over the judges and over everything. When the Holy One blessed be He sought to appoint a High Priest, Moses thought that perhaps he would become the High Priest.
The Holy One blessed be He said to him: ‘Go and appoint a High Priest for Me.’ He said before Him: ‘From what tribe shall I appoint for You?’ He said to him: ‘From the tribe of Levi.’ At that moment, Moses rejoiced.
He said: ‘My tribe is so beloved.’ The Holy One blessed be He said to him: ‘It is Aaron, your brother.’ That is why it is stated: “And you, draw Aaron your brother near to you.” The Rabbis say: All forty years that Israel was in the wilderness, Moses served in the high priesthood.
Some say: He served only during the seven days of inauguration. Rabbi Berekhya says in the name of Rabbi Simon: All forty years Moses served in the high priesthood, as it is stated: “The sons of Amram, Aaron and Moses; [Aaron was separated that he should be most holy, he and his sons forever, to offer before the Lord, to serve Him, and to bless in His name forever]” (I Chronicles 23:13), and it is written: “And Moses, the man of God, [his sons are named among the tribe of Levi]” (I Chronicles 23:14).3The implication of the verse is that Moses’ sons were regular Levites, but he himself functioned as a priest.