This is why Jesus had to rise from the dead 1,900 years ago. No credible person in the present could get away with passing off a modern day resurrection story as the truth.
The only sort of people claiming that supernatural events still occur are the members of the Heaven's Gate cult and their ilk. 1,900 years ago, Christians were that ilk. This is why it took hundreds of years for Christianity to catch on....assuming there really were people around in 33 AD who believed a crucified criminal was God and had just risen from the dead.
BTW, for modern Christians, the rationale for belief is...
"It is said to have happened a long, long time ago. Millions of people over the centuries have claimed to believe it happened. I live in a society wherein many people continue to claim that they believe it happened. Therefore, it must have happened."