I get this question all the time! This is why I chose Catholicism over Orthodoxy: The “keys to the kingdom” in Matthew 16:18-19 refers to the steward position in the Davidic monarchy in the Old Testament, which is mentioned in Isaiah 22:22. The steward was the second-in-command in charge if the king ever left. Jesus is the king in the line of David (as the angel Gabriel told Mary) and He appointed Peter as his first steward in the role of the Roman bishop who is in charge of the Church until Jes