Luke 22:20 → Jeremiah 31:31

Jesus' institution of the Lord's Supper — "This cup is the new covenant (hē kainē diathēkē) in My blood, which is poured out for you" (Luke 22:20) — directly cites the language of Jeremiah 31:31, where Yahweh promises a bĕrît ḥădāšāh ("new covenant") that will surpass the Mosaic covenant broken at Sinai. Jeremiah 31:31-34 is the only explicit "new covenant" text in the Old Testament; it describes a covenant written on the heart rather than stone tablets, with universal knowledge of God and complete forgiveness of sin. Jesus announces that the cup of Passover — itself the memorial of the Exodus covenant — is now the seal of this new covenant, established by his imminent sacrifice. Paul cites Luke 22:20 in 1 Corinthians 11:25 and Hebrews 8:8-12 quotes Jeremiah 31 at length, demonstrating the centrality of this fulfillment claim to NT theology. The new covenant does not abolish the Mosaic covenant but fulfills what it anticipated.