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Did the Aaronic Priesthood Begin Before The Law?
(Exodus 19:22, 18:18-20, 15:25)
by Ed Vasicek
When commenting on God's restriction of even the priesthood from approaching Mt. Sinai in Exodus 19:22, Walter Kaiser (in The Expositor's Bible Commentary) writes: "Certainly this was not the Aaronic priesthood that had not been established as yet. It must be a reference to the 'firstborn' of every family who were dedicated and consecrated to God (13:2)."
Although firstborn sons who were not descendants of Aaron could serve as priests even after the Law was given (as evidenced by the example of Samuel), I disagree with Kaiser's assessment.
When Jethro offers a sacrifice to the Lord to celebrate the deliverance of Israel and their arrival at Mt. Sinai, we find that Aaron was invited to the sacrifice (and mentioned by name) along with the elders of Israel. Coupling this with the instance in which Aaron fashioned the molten calf leads me to conclude that he had been considered a priestly leader for some time.
Notice the counsel Jethro gave Moses in Exodus 18:18-20:
You and the people with you will certainly wear yourselves out, for the thing is too heavy for you. You are not able to do it alone. Now obey my voice; I will give you advice, and God be with you! You shall represent the people before God and bring their cases to God, and you shall warn them about the statutes and the laws, and make them know the way in which they must walk and what they must do.
One must ask, "What laws and statutes?" The Mosaic Law had not been given at this point. Jethro's advice is found in Exodus 18, but the first part of the Law is given in Exodus 20. Some have suggested that Exodus 18 actually belongs later in the book of Exodus. But such relocation theories are usually an agenda-driven suggestion attempting to harmonize a supposed chronological discrepancy. So again I ask, "What laws and statutes did Jethro have in mind?"
The Noahic Covenant and the ancient Priesthood (of which Melchizedek was but one while Jethro was another) were around hundreds of years before Aaron was born. But there is no evidence that Aaron participated in this priesthood while a slave in Egypt.
The best answer is found in the Jerusalem Targum. Its paraphrase and expansion of Exodus 15:25 reads, "And Mosheh prayed before the Lord, and the Word of the Lord showed him the tree of Ardiphne, and he cast it into the midst of the waters, and the waters were made sweet. There did the Word of the Lord show unto him statutes and orders of judgment, and there He tried him with trials in the tenth trial."
The ESV version of Exodus 15:25 reads: "And he cried to the LORD, and the LORD showed him a log, and he threw it into the water, and the water became sweet. There the LORD made for them a statute and a rule, and there he tested them."
Although the Old Testament ambiguously states that God gave the Israelites "a statute and a rule," the Targum demonstrates the Jewish understanding that this meant "statutes and orders of judgment." The Targum of Jonathan enumerates a number of specific commands (though none applying to the priesthood).
Exodus 15:25 is an important yet relatively obscure passage. Just as Jesus breathed the Holy Spirit to His disciples as a preview of Pentecost (John 20:22-23), here the "mini-law" may have been given before the formal giving of the Law (which, incidentally, was probably given on the Day of Pentecost, based on traditional Jewish calculations).
In summary, my theory is this: some of the Law was given before Moses returned to Mt. Sinai. Some of these statutes could have included minimal priestly instruction, instruction which was repeated and expanded upon later in cohesive fashion (when the Law was formally and comprehensively decreed). The information that Aaron's line would become the priestly line may have been included in this prelude.
To put it in modern terms, God seems to have leaked out information about the Law before the news conference!