Prayer with Roman Catholics at a "divine liturgy" (VS. mass) would, I guess, imply that it was lead by Orthodox hierarchs and as long as this is the case and communion was not served to RC's would not be a big deal. However, I am asking if common prayer in general with RC's is considered against the canons or if the canons specifically refer to any divine liturgy or concelebration.
Also, maybe someone more learned than I can show us the exact canons? It's been a while since I've read those specific ones.
In addition, is the RCC considered heretical, schismatic, apostate, or something more murky than this? I ask because of the direct and increasing relations between Orthodoxy and the RCC.
Please do not read into this post either. I am not looking for argument but attempting to learn more about my faith.