Atheists, tell me, a Roman Catholic: why should I become an atheist?

[GUBU]

1) I doubt this one is fake. You don't have to be a philologist to catch the figurative sense here. The priest has always occupied a position of authority, and has often (sadly) abused that authority. Are you suggesting that Innocent III actually taught that priests are gods?

2) They often are. Everything the Pope says is not infallible. Only very specific things, said in very specific ways, said under very specific circumstances can be considered infallible. To give you a sense of how often: there are less than 10 instances of infallible statements given by Popes. That is like once every 300 years.

For example, the latest encyclical of Pope Francis, Laudato Si, does not contain any such statements.

help me understand how to determine a statement to be infallible

If its a) in the bible, b) uttered by the pope or c) uttered by a church council that the pope says is correct. And don't worry if you find contradictory infallible statements, we can make 2+2 equal anything we want, Winston.