Why Do You Think Christianity Is True?

John Piper was recently asked, "Why do you think Christianity is true?" Here's a key part of his response:

How do you, when you want to decide if someone's testimony or witness is true? You weren't there. There were no videos. There was no recording. And you have to decide whether what he's saying happened actually happened....

So when I'm reading the Bible, whether it's the Gospel of John or Romans, I'm asking the question, "How can I credit what's here, both the testimony of the man and the portrait of Jesus?" And I think there is a light that stands forth from the text of the truthfulness of Jesus that is self-authenticating. And there is a kind of character for the writers that stands forth that is authenticating of their solidity and truthfulness, confirming that they're not lunatics or liars.

If somebody said to me today, "Just tell me in 30 seconds why you're a Christian," I would say, "The portrait that I see of Jesus Christ in the Gospels is self-authenticating to me. I cannot meet this man and have him speak like nobody else spoke and not believe him. He wins my trust."

And then if they say, "Ah, but how do you know that that person is not being created by somebody else?" Then I would say, "Then the person creating him is just as phenomenal, and they win my trust. And if they win my trust then they're not lying to me." The Apostle Paul is not a lunatic. I cannot read the 13 letters of Paul and think he's crazy or a liar.

Theologian John Murray once wrote something similar:

In common parlance we say a man commands confidence. We do not trust a man simply because we have willed to, or even because we desire to. And we cannot distrust a man simply because we wish or will to do so. We trust a man because we have evidence that to us appears sufficient, evidence of trustworthiness. When to our apprehension a man presents evidence of trustworthiness we cannot but trust him, even though we hate his trustworthiness and would wish the opposite to be the case. His trustworthiness may be the ruin of what we think to be our interests, but we cannot but trust him.... We cannot but believe in his reliability and truthfulness (Collected Writings of John Murray, 2:237).

What both of these men are saying is that Jesus himself is the compelling reason for faith in him. The truth of Christianity rests on who Jesus is.