C. Michael Patton recently wrote a post about whether Roman Catholics are saved. The subject can be approached from many angles, and I'm not going to address it in much depth in this post. What I want to do is link to other posts I've written on some of the relevant issues.
I disagree with some of what Patton wrote, and there are a lot of problems with the comments that follow his post. On the other hand, Patton makes some good points along the way. And he doesn't address some of the relevant issues, so I don't know where he stands on everything involved. This post is intended to address a broader range of topics than the ones raised by Patton, but his thread offers a recent illustration of what I'm responding to.
One of the most common objections to the idea that Catholicism isn't Christian is that the idea implies too negative a view of pre-Reformation church history. Were individuals like Augustine and Thomas Aquinas not Christians? Where was the church prior to the Reformation? Was it just a small remnant? Did it cease to exist? Would God allow the church to be so diminished, or even cease to exist, for so long? How can belief in justification through baptism, or justification through works in general, constitute a false gospel if so many church fathers and other individuals and groups in church history have believed in such concepts? Were they all non-Christians? Was the gospel lost, or nearly lost, for more than a thousand years? And so on. The line of argument I've just described is an objection that's often raised, and Evangelicals seldom address it well. It came up again in Patton's thread.
I'll begin by summarizing my position. Then I'll provide links to my material on some of the issues involved.
Roman Catholicism is correct on many issues, including most essentials. It does a lot of good in many contexts. But it should be considered a non-Christian system because of its false gospel. It's similar to the Judaizers in many ways. However, some Catholics are Christians in spite of the non-Christian system they're affiliated with. And Catholicism can be included under terms like "Christianity" and "Christendom" in some contexts, when the definitions involved are broad enough to warrant it. A wide diversity of views of justification existed prior to the Reformation, and some individuals and groups weren't consistent on the subject. Justification through faith alone was one of the views that existed during that period. But an individual could be justified through faith alone, yet depart from that view of justification in some manner, as Peter and the Galatians did. Unfaithfulness to the gospel doesn't tell us, by itself, that an individual isn't a Christian. There can be mitigating factors involved. Belief systems are different than individuals, however, and are judged accordingly. There are no mitigating factors involved that would warrant considering the Roman Catholic system orthodox.
Having said all of that, I want to provide some links to posts that go into more depth. These are just representative examples. More could be cited.
Here's a post I wrote about justification through faith alone in the Biblical authors and other pre-Reformation sources, including the church fathers.
I participated in a lengthy discussion of the relationship between justification and baptism in a thread at a Roman Catholic web site in late 2009 and early 2010. In that thread, I discussed some of the Biblical and patristic evidence against justification through baptism. In a post here, I link to that thread and quote some of my comments from it.
And here's a post about the diversity of beliefs, including beliefs about justification, that existed in the years leading up to the Reformation and just after it began.
Regarding how we judge whether an individual is a Christian - a historical figure like Augustine, a Roman Catholic, or somebody else - see here, including the comments section of the thread.
In a thread at Tim Challies' blog in 2009, I explained why I consider the Roman Catholic view of justification a false gospel. Here's a post in which I link to that thread. The post also addresses the claim that justification through faith alone isn't a foundational element of the gospel, since it isn't included in the gospel summary in 1 Corinthians 15:1-4. Patton uses a similar argument in his post I linked above. He appeals to 1 John 4:2. The general principles I lay out concerning 1 Corinthians 15 are applicable to 1 John 4 as well.
These are just some of many examples of the posts at this blog that address such issues. You can find a lot more in our archives, like here.