That depends on what you mean by "true". For instance, 1+1=2 is true. If you thought 1+1=3, then I suppose you could say that 1+1=2 is "not true" for you. However, I wouldn't buy that argument. I think 1+1=2 is true for everyone. No matter how sincerely you thought 1+1=3, you would still be wrong.

I think of Christianity the same way. If Christ really was the Son of God, and really did die forgiving us on God's behalf... then that is true. I'm not judging you. Only God can do that, and only God knows what truth you have come to understand. So only God can judge the sincerity of your conscience. But I can proclaim the truth, any truth, and I will.

Just because you disagree with me does not mean one of us "doesn't think for himself." It just means we disagree. That is all. I understand your frustration though. Way too many Christians judge other people when they have no business doing so.

A Buddist may be able to repent without converting, or he may not be able to. It depends on the person. Repentance is when someone turns from what they know to be sin. That is all. Many Christians try to paint the world with a broad brush and proclaim who is an "unrepentant sinner" and who is not. When it comes to love, treating your neighbor as you treat yourself, judging repentance is relatively easy to do. When it comes to other matters of faith though, it is nearly impossible to know who has a pure conscience before God and who doesn't.

God doesn't reveal everything about Himself to everyone in the same ways. For instance, many cultures don't even have the Bible yet! However, the single, ultimate command in Christianity is to love. That is "the sum of the law." The command is to love God which is like loving your neighbor (Matthew 22:34-40). In fact, it is *exactly* like loving your neighbor (Matthew 25:40). Even non-Christians have the sum of the law written on their consciences (Romans 2:15). Love comes from a pure heart, a good conscience, a sincerity in what you believe. (1 Timothy 1:5)

There is a difference between intentional sin and un-intentional sin. See 1 John 5:16 and also the "deliberate sin" mentioned in Hebrews 10:26. We all have un-intentional sin. "We all stumble in many ways." (James 3). James isn't talking about intentional sins there. He is saying we all have un-intentional error in our thoughts and our lives.

We must, however, avoid intentional sin. That is sincere repentance. You have no way of knowing what any particular Buddist knows is a sin. For all you know, the Buddhist who rejects Christ has not done so intentionally. You have no way to know. Only God knows that, so only God can truly judge if a person has repented.

Matters of faith are a lot harder to judge people over than matters of action, love towards their neighbors. We can judge the truth, and we should. But we cannot always judge people's sincereity concerning how they respond to it.