The New Covenant is also sealed with blood, but it is not sprinkled on the outside of those making the covenant, as happened with Israel. Instead, it is ingested into the innermost parts of the person. Rather than being sealed with the blood of oxen, the New Covenant is sealed with infinitely more precious blood, blood that serves as a testimony of eternal life (see I John 5:6-13), as well as a pledge of God's loyalty to those within the covenant:
Notice that God makes us complete through the blood of the covenant. Christ's blood is a pledge that God made that He will finish His extraordinary purpose - one that goes beyond forgiveness and culminates in our spiritual completion. When we are complete, then Passover will be fulfilled. But the forgiveness of sins comes through the covenant, not before it. Before the covenant, God overlooks - He passes over. When we pledge our loyalty to God through baptism, and accept His covenant after repenting, He then forgives us. When we are put into Christ, we are washed clean (see Acts 2:38; 4:12; 8:36-37; 22:16; Romans 6:3-7, 23; Colossians 2:12; Titus 3:4-7). But the cleansing blood of atonement is only available to those who accept the divine blood of the covenant.
Forgiveness is part of the covenant because we need God's forgiveness throughout the process of being made complete. Neither the Old nor the New Covenant - nor the covenant with Abraham - were preceded by atonement. Instead, God makes covenants with those whose transgressions He has passed over. It is within the covenant, then, that sin is addressed. This is why Jesus proposed the New Covenant to His disciples at that Passover observance even before He died to provide atonement the following afternoon.
As we can see, sin is not the focus of Passover. Instead, God's mercy underlies the fellowship He initiates. The much greater focus is on the ongoing fellowship with the Father and the Son, as well as communion with those who partake of that one, living Bread. It is a memorial of Christ's death that sealed the covenant, as well as a grateful observance of our spiritual abundance and hope because of God's faithfulness. It is a solemn yet joyful celebration of the peace and well-being we have in Christ.
The bread and the wine represent the sacrificial meal, which ultimately is Jesus Christ. God accepts those partaking of this meal, and He is pleased to have them in His presence. The bread of life imparts spiritual strength, and through drinking the wine, we take in the blood of the covenant. That blood is an overwhelming pledge by Almighty God to make complete those who remain faithful, who do not count the blood of the covenant as common (see Hebrews 10:26-29). Both God and the individual are satisfied because of the peace and fulfillment that comes through the divine fellowship that Jesus Christ facilitates.
That's our hope. After He died for our redemption, He was raised by the Father for our hope.
Just to put a capstone on this sermon: It's not just compliance that God wants when we tithe - but GIVING as He gives.