Exodus 24:7-8

"And he took the book of the covenant, and read in the audience of the people: and they said, All that Jehovah hath spoken we will do, and be obedient. And Moses took the blood, and sprinkled it on the people, and said, Behold the blood of the covenant, which Jehovah hath made with you concerning all these words."

"All that Jehovah hath spoken we will do ..." This reaffirmation on the peoples' part that they would indeed obey the word of God followed the reading of the Book of the Covenant in their hearing by Moses himself. "This was Israel's third promise to obey. See Exodus 19:8; 24:3; and Exodus 23:22.[14]

"And Moses took the blood ... and sprinkled it on the people ..." Note that none was sprinkled on the pillars. This double blood-sprinkling was the establishment of the covenant, the covenant being specifically mentioned in connection with the ceremony itself: "This is the blood of the Covenant!" (Exodus 24:8). Significantly, Jesus Christ himself on the night in which he was betrayed instituted the Lord's Supper, saying, "This is my blood of the new covenant, which is poured out for many unto the remission of sins" (Matthew 26:28). Thus, Jesus Christ himself made the blood-shedding to be the establishment of the New Covenant, indicating at the same time that it was the blood-shedding here that established the Old Covenant. This was not part of it, but ALL of it. The fellowship meal mentioned later only celebrated a past event that was already accomplished.

Why was the covenant established in blood? Many reasons could be given, but here are a few:

1. it stressed the serious, even fatal, nature of sin, in that only blood, indicating death, could cleanse it;

2. particularly, it was a type of the sacrifice of Christ "for the sins of the whole world";

3. in God's view of a covenant, "Before it could be in force, a death must have occurred (Hebrews 9:15-17)."[15]

4. Not even the first covenant was dedicated without blood (Hebrews 9:18).

5. This also constituted a reminder that death was the penalty of breaking the covenant.

6. It symbolized the unity between God and Israel, since the same blood was sprinkled upon both, upon God in a figure, at the altar, and upon the people also (Exodus 24:7).
7. "The blood symbolizes the grace of God in man's redemption.[16]