One of the things that persuaded me to become Catholic was the idea that Christ established a Church that has continued into the present day. Once I understood Apostolic Succession and the magisterium, I found this more compelling than the alternative view I had been implicitly raised with and unknowingly accepted.
The alternative view is that Christ started a church but then left it for some unknown reason to fall into error, or worse, that he was too weak or unloving to keep his church from error. He somehow guided this church to codify the Bible infallibly, and to define a few key doctrines correctly (ie, the Trinity), but there was little else that this church did that was correct.
I do remember having that conception of the church, so let me defend my old view for a moment. That view fits with how I imagined Christ’s ministry while he was walking on the earth. He was an itinerant preacher, wandering from place to place, preaching the Gospel and performing miracles. He appeared to be outside of the established Jewish hierarchy, railing against it to discredit it, to encourage people to abandon it and to follow him.
I see now that my picture of Christ’s relationship to the Jewish hierarchy of his day was not correct. Why? Because that hierarchy was established by God, so Christ was not discrediting the hierarchy itself or its authority. He was only discrediting the poor conduct and lack of faith of its members. For example:
Then Jesus said to the crowds and to his disciples, “The scribes and the Pharisees sit on Moses’ seat, so do and observe whatever they tell you, but not the works they do. For they preach, but do not practice…” (Matt. 23:1-3)
Sitting on Moses’ seat is a big deal. It means that the authority structure was established by God. There is no way Christ would encourage people to abandon or disrespect that authority structure while it was still active. It was, however, annulled with the implementation of the New Covenant.
The Catholic claim is that the priesthood of the New Covenant is a continuation of the priesthood of Melchizedek, not of Aaron. Christ is a priest in the order of Melchizedek, and he established a hierarchy that is founded on, and operates through, himself. The Apostles and their successors participate in and express Christ’s priesthood. They operate in persona Christi, in the person of Christ. So when, for example, I go to confession, I am confessing to Christ, not to the priest, strictly speaking. The order of Melchizedek forms the backbone of the Church (read more about this here, starting at 1544).
Christ has kept this hierarchy and the Church it supports free from error in regards to its teachings regarding faith and morals, and to me, this is a miracle. This living Church is the very sort of miracle he would perform. To me, it means that he is a lot bigger and more loving than I originally thought he was.