1 Corinthians 10:16-17

16Is the cup of blessing which we bless [at the Lord’s Supper] not a sharing in the blood of Christ? [Indeed it is.] Is the bread which we break not a sharing in the body of Christ? [Indeed it is.]

17Since 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].