Every covenant that God establishes is accompanied by a sign or symbol. By definition, a covenant is a solemn promise of God to His people, grounded in His character and faithfulness. In the Old Testament, we see this clearly: the global flood would never again destroy the earth, and the sign of this promise was the rainbow. Abraham and his descendants were chosen as God’s covenant people, promised a land, a people, and blessing; the sign of this covenant was circumcision. The Mosaic covenant was accompanied by the Sabbath, a sign of God’s rest and faithfulness. The pattern is unmistakable: every divine promise or covenant in Scripture is confirmed by a visible sign or symbol.

This covenantal pattern continues and finds its fulfillment in Christ. Jesus inaugurates a new and better covenant. At the Last Supper, He declared:

“And he took bread, and when he had given thanks, he broke it and gave it to them, saying, ‘This is my body, which is given for you. Do this in remembrance of me.’ And likewise the cup after they had eaten, saying, ‘This cup that is poured out for you is the new covenant in my blood.’” [Luke 22:19–20]

Notice carefully the two elements: the bread and the cup. The bread is not the sign of the New Covenant; it is a memorial of Christ Himself, calling us to remember His person and work. The cup, by contrast, is the explicit sign of the New Covenant, sealed in His blood. In these elements, Jesus invites us to remember the condition from which we were saved—sinners in need of mercy—and to reflect on the covenant promise of salvation. Every time we partake, we participate in a covenant renewal, recalling both God’s promise and our call to faithful obedience.

It is crucial to understand that when we speak of Communion as a sacrament of covenant renewal, we do not imply that God needs to renew His covenant with us. The covenant of redemption, ratified in Christ’s death, is irrevocable and eternally secure. When Jesus cried out, “It is finished!” He accomplished the covenant, fully effecting salvation for His people. What is renewed is not God’s promise, but our apprehension of it—our faith and gratitude. Covenant renewal is necessary because we are forgetful, prone to doubt, and slow to remember God’s faithfulness.

Martin Luther explains the irrevocability of God’s covenant well:

“Not every vow is called a testament, but only a last irrevocable will of one who is about to die, whereby he bequeaths his goods, allotted and assigned to be distributed to whom he will. Just as St. Paul says to the Hebrews, a testament must be made operative by death… Therefore, wherever in Scripture God’s testament is referred to by the prophets, they are taught that God would become man and die and rise again, so that His Word, in which He promised such a testament, might be fulfilled and confirmed… That little word ‘testament’ is a summary of all God’s wonders and grace fulfilled in Christ.” (Works, Vol. 1, pp. 233–234)

To deny God’s covenant would be to deny the testament ratified by Christ’s blood. This is the believer’s strongest assurance: God will never break His Word. We are called to remember this covenant faithfully, which is precisely the purpose of the bread and the cup: to remind us, renew our hearts, and strengthen our covenantal faithfulness.

The New Covenant at the Last Supper can be understood in six covenantal elements:

The issuer of the covenant: Jesus Christ
The recipients of the covenant: His people, the Church
The content of the covenant: “This is my body… This is my blood… a new covenant”
The sign of the covenant: The bread and the cup
The blessing of the covenant: Redemption and forgiveness of sins
The obligation of the covenant: To remember Christ and live in covenantal obedience, walking in His grace and truth (cf. 1 Corinthians 11:26)

Thus, Communion is far more than a remembrance of Christ; it is a covenantal act. Each time we partake, we acknowledge the work of Christ, affirm the promises of the New Covenant, and renew our commitment to covenantal faithfulness, empowered by the Holy Spirit, to live in obedience to God’s Word.