Exodus 24:7-8

7Then he took the Book of the Covenant and read it aloud to the people; and they said, “Everything that the Lord has said we will do, and we will be obedient.”

8So Moses took the blood [which had been placed in the large basins] and sprinkled it on the people, and said, “Behold the blood of the covenant, which the Lord has made with you in accordance with all these words.”