The ecclesiological model of Church as an Institution holds that the Catholic Church alone is the "one, holy, catholic and apostolic Church", and is the only Church of divine and apostolic origin led by the Pope. This view of the Church is dogmatically defined Catholic doctrine, and is therefore de fide. In this view, the Catholic Church— composed of all baptized, professing Catholics, both clergy and laity—is the unified, visible society founded by Christ himself, and its hierarchy derives its spiritual authority through the centuries, via apostolic succession of its bishops, most especially through the bishop of Rome (the Pope) whose successorship comes from St. Peter the Apostle, to whom Christ gave "the keys to the Kingdom of Heaven".