I believe that it would be wrong for you to not take communion because someone who is a "heretic" has partaken. That should not affect YOUR ability to receive the Sacrament correctly. Just ask your priest how he feels about you denying yourself the Eucharist when you are spiritually prepared (as much as us sinners can be!) to receive it.
Besides, you don't think this happens in every church where there are a number of people attending? You just are not aware of everyones beliefs.
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They say that I am bad news. They say "Stay Away."
TomS,
Surely you cannot know what everyone believes, but, if they confess an errant form of Orthodoxy, it is the priests duty to correct them and not commune them.
I believe that while it is primarily the priests responsibility to discern, as much as he can, the preparedness of each individual, I could not in good conscience share the cup of salvation when I knew the priest was knowingly communing someone who was not Orthodox.
