It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.
Common participation in the Eucharist can only be a final outcome of ecumenic dialogue, not the starting point.
Given the fact that most religions share basic values, it is most unfortunate that religious people can be played off against each other so easily. One possible reason for this may be that people do not know enough about other people's beliefs.