Technology that could have existed

The church doesn't need to argue against anything. Their religion teaches "blind faith," which is impossible to argue with.

If you present them with evidence against their religion, they say "God put this here to test my faith." You could have a letter from God himself telling them that he's just a fraud and he doesn't really do anything or give a shit about them and they wouldn't believe it.

Most priests I knew taught us not to have blind faith, but to question things and learn about our faith.

The church doesn't need to argue against anything. Their religion teaches "blind faith," which is impossible to argue with. If you present them with evidence against their religion, they say "God put this here to test my faith." You could have a letter from God himself telling them that he's just a fraud and he doesn't really do anything or give a shit about them and they wouldn't believe it.

Yes, all true, however there are a significant amount of semi-rational people who do question portions of their faith.