One convincing evidence for Christianity is that it is the only religion in the world that can boast of a 100% fulfilled prophecy rate. While this is a mostly defensible claim, there are some attempts to counter it. For example, there are three places in the Bible wherein Jesus promises that some of those standing there would not taste death until they saw the Kingdom of God. Many unbelievers interpret this to mean that Jesus was saying He was going to come back before all the disciples had died. Since the world continues to this day, long after the disciples had all died, this prophecy is said to have failed.
However, there is compelling evidence that Jesus was not referring to His second coming. Every instance of this prophecy is immediately followed up by an event known as the Transfiguration.
During the transfiguration, some of the disciples, who had not yet tasted death, follow Jesus up a mountain, where He speaks with a glorified Moses and Elijah, and He Himself is transfigured into a glorified state. The sight is so spectacular that the disciples actually offer to build three tabernacles, one for Jesus, one for Moses and one for Elijah. Moses and Elijah then leave, and Jesus becomes pre-glorified again.
Thus, Jesus' prophecy was fulfilled in the transfiguration. Some of the disciples caught a glimpse of the Kingdom of God before they tasted death.