I don't think it's possible currently, but maybe a feature we can suggest for the future.

As for why your post got downvoted, it seems that Lemmy is majority Atheist, based on the amount of posts I see on "All / Hot". Your community may be targeted by a small group if this is a recurring event.

I don't have a good solution for you in the meantime. I know that communities can be blocked by instances, so you may be able to get in contact with lemmy.ml, beehaw, lem.ee, etc. instance owners and ask them to block your community from their feeds, or something like that.