I am trying to track down the reference to a story of a Jew who was studying Catholicism with the help of a priest. The Jew decided to go to Rome and he saw all the scandal going on. (During a time of great scandal possibly in the middle ages). When he came back the priest said you probably don’t want to convert now seeing the scandal. The Jew replied on the contrary if God was not behind the organization it would have collapse years ago. I want to use this story in a project but I don’t have any details about it. Thanks if anyone knows anything about it.
It's The Decameron, Day 1,Tale 2, by Giovanni Boccaccio that you're looking for. It's not really the exact story you outlined, but I don't think there's any story that's closer.
Thanks. It is what I was looking for. I didn't quite remember everything correctly but I was thinking the Jew's name was Abraham but I wasn't sure.