Exodus 24:5

After the foundation and soil had been thus prepared in the place of sacrifice, for the fellowship which Jehovah was about to establish with His people; Moses sent young men of the children of Israel to prepare the sacrifices, and directed them to offer burnt-offering and sacrifice slain-offerings, viz., שׁלמים, "peace-offerings (see at Lev 3:1) for Jehovah," for which purpose פּרים, bullocks, or young oxen, were used. The young men were not first-born sons, who had officiated as priests previous to the institution of the Levitical priesthood, according to the natural right of primogeniture, as Onkelos supposes; nor were they the sons of Aaron, as Augustine maintains: they simply acted as servants of Moses; and the priestly duty of sprinkling the blood was performed by him as the mediator of the covenant. It is merely as young men, therefore, i.e., as strong and active, that they are introduced in this place, and not as representatives of the nation, "by whom the sacrifice was presented, and whose attitude resembled that of a youth just ready to enter upon his course" (Kurtz, O. C. iii. 143). For, as Oehler says, "this was not a sacrifice presented by the nation on its own account. The primary object was to establish that fellowship, by virtue of which it could draw near to Jehovah in sacrifice. Moreover, according to Exo 24:1 and Exo 24:9, the nation possessed its proper representatives in the seventy elders" (Herzog's Cyclopaedia). But even though these sacrifices were not offered by the representatives of the nation, and for this very reason Moses selected young men from among the people to act as servants at this ceremony, they had so far a substitutionary position, that in their persons the nation was received into fellowship with God by means of the sprinkling of…

Moses, as mediator between God and Israel, having received divers laws and ordinances from God privately in the three foregoing chapters, in this chapter, I. Comes down to the people, acquaints them with the laws he had received, and takes their consent to those laws (Exo 24:3), writes the laws, and reads them to the people, who repeat their consent (Exo 24:4-7), and then by sacrifice, and the sprinkling of blood, ratifies the covenant between them and God (Exo 24:5, Exo 24:6, Exo 24:8). II. He returns to God again, to receive further directions. When he was dismissed from his former attendance, he was ordered to attend again (Exo 24:1, Exo 24:2). He did so with seventy of the elders, to whom God made a discovery of his glory (Exo 24:9-11). Moses is ordered up into the mount (Exo 24:12, Exo 24:13); the rest are ordered down to the people (Exo 24:14). The cloud of glory is seen by all the people on the top of mount Sinai (Exo 24:15-17), and Moses is therewith God forty days and forty nights (Exo 24:18).