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?
All Commentaries on 1 Corinthians 10:16 Go To 1 Corinthians 10
George Leo Haydock
The chalice of benediction Which the priests bless or consecrate, is it not the communion of the blood of Christ? And the bread which we break, (so called because of the outward appearance of bread) is it not the partaking or communion of the body of the Lord? See St. Chrysostom here, hom. xxiv. p. 396. and p. 400. See also the Annotations, Matthew xxvi. 26. (Witham)
Here the apostle puts them in mind of the partaking of the body and blood of Christ in the sacred mysteries, and becoming thereby one mystical body with Christ. From whence he infers, (ver. 21.) that they who are made partakers with Christ, by the eucharistic sacrifice, and sacrament, must not be made partakers with devils, by eating of the meats sacrificed to them. (Challoner)