“The Church is apostolic because she is founded on the preaching and prayer of the apostles, on the authority that was entrusted to them by Christ himself. St Paul writes to the Christians at Ephesus: “You are no longer strangers or sojourners, but you are fellow citizens with the saints and members of the household of God, built upon the foundation of the apostles and prophets, Christ Jesus being the cornerstone” (Eph 2: 19-20); that is, he compares Christians to living stones that form an edifice that is the Church, and this edifice is founded on the apostles, who are like columns, and the cornerstone that carries it all is Jesus himself. Without Jesus the Church cannot exist! Jesus is the foundation of the Church — the foundation! The apostles lived with Jesus, they listened to his words, they shared his life; above all they were witnesses of his death and resurrection. Our faith, the Church that Christ willed, is not based on an idea; it is not based on a philosophy. It is based on Christ himself.”
General Audience, October 16, 2013.