We trust that Holy Spirit succeeded in guarding Faith to be pure and passed down as pure. In the end, Satan is father of all lies and as such we don’t believe he was successful in infiltrating Church doctrine which is “pillar and foundation of Truth”.
Yes, it makes sense that if God gave us a trustworthy Book, the living Christ would also give us a trustworthy Church. Christ is alive, as is His Body. The Truth is:
written not with ink but with the Spirit of the living God, not on tablets of stone but on tablets of human hearts. (2 Corinthians 3:3).
Yet His Word is also:
“living and active, sharper than any two-edged sword, piercing to the division of soul and of spirit, of joints and of marrow, and discerning the thoughts and intentions of the heart” (Hebrews 4:12), "and able to make you wise for salvation through faith, which is in Christ Jesus." (2 Timothy 3:15)
But in regard to the one, holy, catholic, and apostolic Church, is this something institutional or something mystical? If, on the one hand (speaking hypothetically), there is a theologically liberal Catholic who no longer accepts the essential creeds of the Church, and on the other, there is a Protestant who has accepted those things that the Catholic Church itself deems to be sufficient for salvation, which of these two is truly part of the Body of Christ?
It seems that what we apply to the visible Catholic Church we can also apply (from a different perspective) to the invisible mystical Church–in which case, its universality cuts across denominational lines. This mystical Church is held together by the Spirit, through whom God is “all in all.”
In regard to Peter, I do believe he was the founding Rock, but of course, it was Christ who built the Church. I don’t, however, see scriptural evidence for his successors. I think one would have to accept
a priori the authority of the Catholic Church on that matter.
According to a Protestant understanding, the Holy Spirit is the only true interpreter of God’s Word. If we are in Christ, we have His Spirit. But we, being sinners by nature, still wrestling with sin, the flesh and the Devil, often “quench His Spirit.” We do this regardless of whether we are Catholic or Protestant. Some Catholics are further on the road to sanctification than some Protestants, and some Protestants are further on that road than some Catholics.
I do, however, recognize that among Protestants, especially among those who lack an institutional authority structure, there is massive doctrinal confusion. So on a practical level, I see the real advantage of the Church hierarchy that exists for Catholics, Orthodox, Anglicans, and Lutherans.
I’m just thinking out loud. I welcome your responses.