Who are the priests mentioned in Exodus 19:22 & 19:24? God did not appear to start the Hebrew priesthood until Exodus 28:1

Question

Since God does not seem to establish the Hebrew priesthood until Exodus 28:1, who are the priests referring to in Exodus 19:22, 24?

20 And the Lord came down upon mount Sinai, on the top of the mount: and the Lord called Moses up to the atop of the mount; and Moses went up.

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24 And the Lord said unto him, Away, get thee down, and thou shalt come up, thou, and Aaron with thee: but let not the priests and the people break through to come up unto the Lord, lest he break forth upon them.

Later, in Leviticus 1:5 Aaron and his sons (from the Levite tribe) are designated as being the first priests for the Hebrew nation (Israel). Numbers 3:12 indicates that the males from the Levite tribe are to serve as priests instead of the firstborn, as mentioned in Exodus 13:1 & 22:29.

Answer 1

Before God designated the Levites as priests, the firstborn were priests after God struck down the firstborn in Egypt.

11 And the LORD spoke to Moses, saying, 12 “Behold, I have taken the Levites from among the people of Israel instead of every firstborn who opens the womb among the people of Israel. The Levites shall be mine, 13 for all the firstborn are mine. On the day that I struck down all the firstborn in the land of Egypt, I consecrated for my own all the firstborn in Israel, both of man and of beast. They shall be mine: I am the LORD.” (Num. 3:11–13, ESV)

22. the priests According to Exodus 28 and 29, the priesthood was not established in Israel until after the Sinaitic revelation, which would make the present reference to priests, like that in verse 24, an anachronism. Many modern scholars regard these verses as reflecting a different strand of tradition about the origins of the priestly institution. Jewish commentators understood “priests” here as referring to first-born males, in that the latter functioned as priests until they were replaced by the Aaronides, as recounted in Numbers 3:11–13 and 8:16–18. [Exodus 13:1-2,13; 34:20] -- Sarna, N. M. (1991). Exodus (p. 107). Jewish Publication Society.

Answer 2

When God established the Israelite covenant in Ex 19-23, there was no formal priesthood. The priests where the firstborn of each family.

However, very soon after the Israelite covenant, God then established the Levitical Covenant as defined and referenced in Lev 1-9, 16, 21-27 , Num 3, 4, 8, 18, 25:10-13, Deut 33:8-11, Neh 13:29, Mal 2:4-8.

The Levitical covenant is stated in Num 3:11-13, 25:12 where God takes the Levites (especially the line of Phineas as High Priest) instead of the all the firstborn of each family, thus changing the (informal) priesthood from the firstborn of each family to the (formal) priesthood of tribe of Levi. Several Bible writers refer to this Levitical Covenant including:

• Neh 13:29 – “the covenant of the priesthood and the Levites”
• Jer 33:18, 21 – “covenant with the Levitical priests.”
• Mal 2:4-8 – “the covenant with Levi”
• Num 25:10-13 – the eternal covenant of priesthood was also a covenant of peace and a covenant of “salt” (Num 18:19), ie, very solemn and eternal.
• Isa 54:10 & Eze 34:25 also describes the covenant of peace with the Levites

From other Bible passages we can see what the Levitical covenant was.

• The purpose of the Levitical covenant was to teach and inculcate the plan of salvation (Deut 33:9, 10, Heb 9:8, 9, 11-14, 10:1-3, Col 2:16, 17). That is, it symbolically taught about salvation by grace through the coming Messiah via His substitutionary death in the place of the sinner. Thus, the sacrifices, Levites, priests and High Priest became a type of Jesus in various ways.
• A promise by God to set them apart, ie, make them “holy” (Num 3:12, 13), to be a substitute for the first born in Israel, and to have the primary responsibility for caring for the sanctuary, its ritual services and sacrifices, maintaining and transporting its equipment. Ex 32:25-29. In this way, they became the priests of Israel. All these regulations were contained in Lev 1-9, 16, 21-27.
• Thus, the Levites enjoyed a “blessed” (and privileged) status. Ex 32:29, Mal 2:5.
• The book of Leviticus (and Num 1 & 18) sets out the responsibilities of the Levites in operating the ceremonial rites and sanctuary services and caring for the sanctuary equipment. See also Num 1:53, 18:2, Deut 10:8, 31:9, 25, Josh 3:3, 2 Sam 15:24, 1 Chron 15:26.
• The token/sign (Heb: “oth”) of the Levitical covenant appears to have been the unleavened bread at the annual festival (Ex 13:6, 9, 16, Lev 24:8).

The formal change from family-firstborn-priests to Levitical priesthood was done using the mechanism of the redemption money as described (in detail) in Num 3:40-51 and Num 18:14-16.