What evidence did the popes use to support their claim to be the head of all the Church?

The popes used several pieces of evidence to support their claim to be the head of all the Church.

1. Succession from St. Peter: The popes claimed to be the direct successors of St. Peter, who was appointed by Jesus Christ as the leader of his disciples and the head of the Church. They argued that this succession gave them a special authority and legitimacy to lead the Church.

2. Universal jurisdiction: The popes claimed that they had universal jurisdiction over the entire Church, based on their role as the successors of St. Peter and the Vicar of Christ on Earth. They argued that this authority was granted to them by God and could not be challenged by any earthly authority.

3. Papal infallibility: The doctrine of papal infallibility, as defined by the First Vatican Council in 1870, stated that the pope is preserved from error when he speaks ex cathedra (from the Chair of Peter) on matters of faith and morals. The popes used this doctrine to support their claim to be the ultimate authority in doctrinal matters within the Church.

4. Tradition and historical precedent: The popes pointed to centuries of tradition and historical precedent to support their claim to be the head of all the Church. They argued that the role of the pope as the supreme authority in the Church had been recognized and accepted by believers for centuries, and that this tradition should continue.

Overall, the popes used a combination of theological, historical, and doctrinal arguments to support their claim to be the head of all the Church.