The term "covenant" refers to the historic event at Mount Sinai when the tribes of Israel were formed into one people (Exodus 24:1-11). That covenant was in blood, the blood of animals that were offered in sacrifice. For Israelites and other ancient peoples, blood was the symbol of life. Sprinkling the blood of the sacrificial animals on the altar and on the people symbolized the union of God and people, now sharing in the one life that was offered to God. So it is that the covenant at Sinai formed the people of Israel into a people of God.

The cup of the Lord's Supper was not just a renewal of the Sinai covenant. It was the "the new covenant," a reference to Jeremiah 31:31-34, which announced "a new covenant" with the law inscribed not on tablets of stone but on people's hearts and with God forgiving the people's sins. The "new covenant" established by Christ would not be in the blood of animals, but in his own blood, "which would be shed for you." It would be established in the sacrificial blood of Christ, the Passover Lamb (see 22:7).

When at the Lord's Supper Christians do what Christ did–namely, take the cup, give thanks and give it to one another–they join Christ in offering their own blood for others. They renew the new covenant in Christ's blood. They forgive one another, extend peace to one another and strengthen the covenant relationship that makes them one people of God.

Dining in the Kingdom of God
Eugene LaVerdiere, S.S.S.