'Communion' in the Bible

The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ?

Since there is one bread, we [believers] who are many are [united into] one body; for we all partake of the one bread [which represents the body of Christ].

See Israel according to flesh: are not they who eat the sacrifices in communion with the altar?

But that what the nations sacrifice they sacrifice to demons, and not to God. Now I do not wish you to be in communion with demons.

Do not be deceived: “Bad company corrupts good morals.”