Question:
Answer:
You are correct in noting that St. Peter proclaims Jesus as the cornerstone, without which there could be no Church (Acts 4:11, 1 Pet. 2:6-7).
The reference to Jesus as the cornerstone comes from Old Testament passages like Psalm 118:22 and Isaiah 8:4, and refers to the sanctuary or Temple of God where the Israelite people worshipped. In other words, Jesus is the new Temple of a New Covenant form of worship (John 2:18-22), who was sadly rejected by many. Without Jesus, there could be no fulfillment of Israel, including a new form of worship centered on Jesus and his Sacrifice of Calvary and its sacramental re-presentation in the celebration of the Mass (Luke 22:19-20), vs. the Old Covenant sacrifices offered at the Temple in Jerusalem that could not provide eternal salvation.
And so there could be no Church, which is the fulfillment of Israel, without Jesus as the cornerstone of the New Covenant and its salvific worship. And yet Jesus chooses Peter as the rock (Aramaic: kepha) upon which to build his Church (Matt. 16:18-19).
Properly understood, then, it’s a both/and, with Jesus as the cornerstone of the New Covenant fulfillment of Israel, and Peter as the rock upon which he builds his Church.
For more on Peter as the rock, see our tracts “Peter the Rock,” “Peter and the Papacy” and “Pillar of Fire, Pillar of Truth.”