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If it had not been for the abuse of this passage by the Roman Catholic Church, it is unlikely that any doubt would have arisen that the reference is to Peter. But the foundational rock is Peter as a representative apostle (v. 15 note), whose confession of Christ has been revealed to him by the Father. As Peter himself later declares (1 Pet. 2:4–8), all believers have become “living stones” by virtue of their association with Christ, with the apostles as the foundation because they receive and relay new covenant revelation (Eph. 2:20, 21; 3:5; Rev. 21:14). When Peter says that Jesus must not go to the cross, he is not called a foundation rock but a stumbling block.