In the past couple of months two prominent Evangelicals, Francis Beckwith and Robert Koons, (re)converted to the Catholic Faith. They, as many other Protestants do, remarked that the Reformation stands and falls by the doctrine of Justification. They say that if Sola Fide is wrong, all of Protestantism is wrong. Beckwith and Koons rightfully discovered that Sola Fide was false and returned home to the One Holy Catholic and Apostolic Church. Far from discrediting their paths back to the True Church, I feel that Sola Fide is not the primary issue. Rather it is secondary. For me, the issue that drives all the rest is the issue of authority.
The reason for this is rather simple and quite logical. If the Catholic Church is correct in her claim to teach infallibly and authoritatively, then logically all the other doctrines are a result of this claim. If Christ truly passed on His authority to the Church, which He did, then the Catholic Church truly teaches what is Truth. The Church’s authority comes from Christ and is protected by the Holy Spirit who leads Holy Mother Church into all truth. Thus, whatever the Church authoritatively declares about Justification, Salvation, and so forth, is none other than the truth. Also, if a person rejects the authority of the Catholic Church, they reject none other than Christ, from whom the Church’s authority flows!
This is something I realized as an Anglican. The issue of authority is key. Once I realized that the authority of Christ resides with the Catholic Church, I had no choice but to become Catholic! Christ said to Peter, "You are Peter and upon this rock I will build my Church." Christ also told Peter to feed His sheep. Our Lord did not say to Saint Augustine of Canterbury that He would build His Church upon him. Nor did He say likewise to Henry VIII or to Martin Luther, John Calvin, Ulrich Zwingli, or Charles Wesley (John Wesley never left the Anglican Church) for that matter! We can easily see the effects with Anglicanism and the other mainline Protestant denominations of a false claim to authority.
The Catholic Church is the only entity given authority to it by Christ. For the Catholic Church is none other than the fulfillment of the Davidic Kingdom and Jesus Christ is none other than the heir to the Davidic throne who’s reign shall have no end. The Kingdom is the Church! This can not be stressed enough. Christ restored the Davidic Kingdom in the Church and made Peter His Prime Minister (an office which is successive). And like all of the Prime Ministers in the Davidic Kingdom, Peter has the highest authority second only to the King himself, who in the Kingdom of the Church is Christ! Our Lord Christ the King gave Peter the Keys to the Kingdom. The Keys represent the authority of the Kingdom. Like the office of Prime Minister (the Pope), the Keys are also successive. When the See of Peter (the See of the Prime Minister) speaks on matters of Faith and Morals, he speaks with the authority of Christ!
This is an essential reality for our separated brethren to understand. In leaving the Church, they leave the Kingdom! This may sound drastic, and it is. All the more reason why it is of the utmost necessity for our separated brethren to come Home. To once again be united in the Kingdom of God which is the One Holy Catholic and Apostolic Church.