>The Trinity is a mystery and nobody can understand it
>But if you don't understand it differently from how we don't understand it you are going to be tortured in Hell for all Eternity
seems a bit arbitrary
Catholics also do this for a few other "mysteries", but the Trinity is the most apparent.
I would personally rather spend eternity in a hell filled with earnest Mormons and Unitarians than a heaven filled with Catholic child rapists.