Christian:

Why is it more probable that your god exists than man made him up?

We have an exceptionally high prior probability that your god is false given that we both believe that every other god claimed to be true (before and after) is false. Thus, on prior probability, the JC God is HIGHLY unlikely to exist. How does the Christian overcome this? They have to provide high CONSEQUENT probability. ie Evidence. But this is poor. Let’s take the four Gospels, written by unknown people at unknown dates in unknown places with ex post facto agendas to evangelise, at least 40 years after the person they are writing about and whom they have never met, has died.