There are a lot of competing truth-claim systems in the world. How do we know that we as Christians are believing what is true and are not deceived? The answer is three-fold.
First, Christianity is only as true as the person of Jesus. He fulfilled prophecy, claimed to be God in flesh, performed many miracles, died, and physically rose from the dead. Christianity is about Jesus, his claims, and his deeds. It is based on him and it is only as true as he is true.
Second, Christianity is consistent with reason, facts, and shows evidence of God's inspiration in the Bible.
Third, all other religious systems are either unverifiable or irrational in their teachings.
The person of Jesus
For the Christian, the ultimate expression of truth is found in the person of Jesus who said, ""I am the Way, the Truth, and the Life and no one comes to the father but through me..." (John 14:6). Jesus, who claimed to be divine, performed many miracles, and rose from the dead said that he alone was the Truth. He was either right or wrong. There is no in-between. If Jesus is wrong, then Christianity is a wrong. If Jesus did not rise from the dead, then we should abandon our faith because he would be no different than anyone else. If Jesus is not God in flesh, then we should denounce him as a madman because you can't claim to be God and be sane -- unless the claim is true. Therefore, if what Jesus said about himself is true, then Christianity is true.
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