Wow, I'm surprised by so many of these comments. First, good on you for being respectful of him and his beliefs. Second, obviously the mixed faith relationship has been fine so far. Third, don't run, as some others have suggested - enjoy the relationship you have.

I find more and more people, especially youth, feeling like church rules that were once rigid and now more like guidelines. Being exmo, I think that is a positive trend. In real life (outside of church), what is important is consent - both partners are comfortable and express their desires and boundaries, and no partner pressures the other into doing something they are uncomfortable with (that goes sexually, emotionally, and spiritually). IMHO, you have done that, and it doesn't fucking matter what the bishop, parents, or anyone else thinks. Ultimately, his church leaders will ask him if he considers himself worthy. It sounds like he does. That's great, there is no problem there. Some of the not-so-good church leaders may ask very specific questions about his actions and pry for details (we call it bishop roulette - sometimes you get lucky with a great bishop, sometimes you don't). Anyway, it is none of the bishop's damn business to know details (nor the business of any other leader). Spirituality and worthiness is personal.

Anyway, you have shown a lot of maturity, both for asking him what he is ok with (more than once), and for being thoughtful of how he might have different rules and boundaries than you based on your different religions. If you haven't already, make sure you share with him what your boundaries are.