The Catholic Argument from History

There are a lot of ways of establishing that the Catholic Church is correct.  One way is to show that the New Testament Scriptures describe a single, visible, authoritative Church capable of settling disputes.  When we find that governance in the Church was headed by the Apostles, with one Apostle (Peter) guiding the other Eleven, that's good evidence that the Catholic Church was the Church Christ founded (Mt. 16:17-19) and intends us to be part of (John 17:20-23).

For some people, that'll do the trick.  They'll read John 6 on the Eucharist, or notice Apostolic Succession in Acts 1, or Petrine primacy in Matthew 16 and Acts 2 and Luke 22 and so on, and they'll have a Eureka! moment - asking themselves, 'how have I read these Scriptures so many times, and never noticed that?'  It's an "Emmaus" moment, when you suddenly discover a Truth you'd never seen before in Scriptures you may well have memorized.  But there are other Christians who look at passages of Scripture which I think spell out core Catholic doctrines, and they just don't read them that way.  For those folks, let's look at a different way of establishing the Catholic Church.

Step One: At One Point, The Global Church Held Catholic Beliefs

To see what I mean above, take four common Protestant doctrines:

1. Baptism is just symbolic (that is, it's not regenerative, and the Holy Spirit doesn't actually cleanse us through it);
2. The Eucharist is just symbolic (it's not actually the Body and Blood of Christ); 
3. Justification is just forensic (we're declared righteous by God, but we're not actually made righteous through the Holy Spirit); and 
4. The Bible is composed of the 66-Book Protestant canon.

To my knowledge, every Protestant denomination holds to at least one of these four doctrines, and many denominations hold to all four.  Now contrast these views with history.

Forget whatever you happen to think about Baptism, the Eucharist, justification, and the canon of Scripture.  At this point, we're just determining what the whole of Christianity used to teach, rather than whether these teachings were right or wrong (we'll turn to that, next). To my knowledge, even Protestants will concede that the visible Church was Catholic during a long period prior to the Reformation.  And although it's true that there were eventually Coptics and Orthodox as well, on all four of the above doctrines, none of them take the Protestant view, either.

So at a bare minimum, we can say that the historic visible Church universally denied all four of the Protestant doctrines above.  In fact, the evidence suggests much more than that -- it suggests that there are centuries of Christianity in which a Protestant would be hard-pressed to find to find a single orthodox Christian who held to any or all four of the above doctrines.  Let's look at each, very briefly: 

1. On Baptism, the Protestant history Philip Schaff, in his History of the Christian Church, Volume II: Ante-Nicene Christianity. A.D. 100-325, writes in the section on "The Doctrine of Baptism" that "This ordinance was regarded in the ancient church as the sacrament of the new birth or regeneration," and that its "effect consists in the forgiveness of sins and the communication of the Holy Spirit." Again, this is A.D. 100 - 325.  The situation remains the same for centuries more, until after the Reformation in the 1500s.
2. On the Eucharist, the Protestant historian J.N.D. Kelly concedes that during the early Church period, “Eucharistic teaching, it should be understood at the outset, was in general unquestioningly realist, i.e., the consecrated bread and wine were taken to be, and were treated and designated as, the Savior’s body and blood.” (Early Christian Doctrines, 440).  Again, this didn't change for centuries afterward.
3. On forensic justification, the Calvinist scholar Alister McGrath concedes that the "Reformation understanding of the nature of justification - as opposed to its mode - must therefore be regarded as a genuine theological novum."  Francis Beckwith, in Return to Rome, does a good job of handling the early Church Fathers who are sometimes used to defend forensic justification - he shows quotes from each proving that their views weren't the Protestant one at all.
4. On the canon of Scripture, I've addressed it here in greater depth. So far, no one's been able to find a single early Christian who owned or used a 66-book Protestant Bible.

You'll be hard-pressed to find any early orthodox Christian who doubted or denied that (1) Baptism actually regenerated you and made you a Christian, (2) the Eucharist was truly the Body and Blood of Christ, and (3) in justification, God declares us "holy" by actually making us holy, just as you'll be hard-pressed to find an early Christian who (4) ever owned or used a 66-book Bible.

Step Two: This Leaves Only Four Possibilities

Given the above, what should we make of it?  Well, it's theoretically possible:

1. That the issues of Baptism, the Eucharist, justification, and the canon of Scripture aren't "essential" doctrines;
2. That the above are essential doctrines, so for long periods of time, no Christian got any of these issues right;
3. That the above are essential doctrines, so the only true Christians were the dissenters;
4. That the Catholic Church was, and is, right on these four issues.

The first three of these are very problematic:

1. The issues of Baptism and justification go to the very heart of how we're saved, and how we become Christians. For Protestants, the canon of Scripture determines where all other doctrines come from, so it's the single most important doctrine.  And on the Eucharist, it's either truly God or an idol Catholics worship.  These seem to be some of the most central questions of Christianity. If these aren't "essentials," it's hard to see what is.  So this produces a theological relativism.  Furthermore, if these aren't essentials, the Reformation was over non-essential issues, and is a wound that should be healed by a return to the Church.
   
2. If all of Christianity could get these core doctrines wrong, we're faced with two problems.  First, Christ appears to promise in Scripture that He and the Holy Spirit will perpetually guide and guard the Church (see the lists of Scripture references here and here).  It's hard to rectify the notion that the Holy Spirit will guard the Church, and the notion that the Holy Spirit would allow the entire Church to fall into apostasy. But the second problem is just as ominous: if a Protestant claims that the entire global Church fell into heresy without knowing it, how can we say that's not the case today?  So this produces theological agnosticism, where no one can even say if the Christianity Christ founded exists on Earth.
   
3. This is essentially the argument that the only good Catholic is a bad Catholic. There are a number of problems.  Of those who denied the claims of Catholic Christianity but stayed in the Church, we're dealing with people who lived a lie. That's not just being a bad Catholic, but a bad Christian. As Christ says in Matthew 5:37, let your "yes" be a "yes," and your "no" be a "no."  Those who declare "yes," while believing "no" are lying.  Of those who denied the claims of Catholic Christianity and left the Church, we know who these people were, historically speaking. Most importantly, they didn't affirm the four doctrines above. (The third approach, that there was an unknown group of true Christians living in the mountains somewhere, is handled here).  So this produces theological self-refutation, because you would have to claim that the only true Christians were either those people Protestants denounce as heretics or those people who lived their lives denying their religion.

The remaining choice is that the Catholic Church is right.  

Conclusion

To state it positively:

• Christ promised that He and the Holy Spirit would preserve the Church;
• Historically, the Church has been incredibly clear (1) that Baptism is regenerative, (2) that the Eucharist is the true Body and Blood of Christ, (3) that the Holy Spirit makes us truly justified, and (4) that there are more than 66 Books of the Bible;
• Even if we don't understand how these things are true from Scripture, we can know that they're true, because the Church said so, and God protects the Church, and we believe in God.

Any contrary reasoning seems to run into some quite severe problems.