How does the Petrine theory support Roman Catholic teaching about papal authority?

The Petrine theory is foundational to the Roman Catholic teaching on papal authority, asserting the theological legitimacy of the pope's ministry and primacy. This theory posits that the Apostle Peter was the first pope and that his authority has been passed down through his successors, the bishops of Rome.1

The theory draws support from Jesus Christ's words in the Gospel of Matthew, specifically where Jesus states, "you are Peter, and on this rock I will build my church" (Matthew 16:18), and when he bestowed the "keys of the Kingdom" upon Peter. These passages are interpreted to mean that Christ established Peter as the prince of the Apostles and the visible head of the church, granting him a primacy of jurisdiction that was intended to pass to his successors.12

In essence, the Petrine office, held by the pope, serves as the link between the church's apostolicity (its connection to Peter) and its catholicity (its unity and universality). This doctrine was formally defined as dogma during the First Vatican Council in 1870, stating that the pope, as the successor of St. Peter, cannot err in definitive statements concerning faith or morals when speaking ex cathedra (from his chair as supreme teacher). This understanding underpins the concept of papal infallibility within Roman Catholicism.134