1 Corinthians 10:16

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? (KJV)

Then: Baker (p. 147) has readers realize Paul is beginning a series of six rhetorical questions. Two are here. Hayes (p. 167) explains that Corinthians who realize that eating in a church communion (fellowship, friendship, and koinonia) obviously reveals a relationship with Christ, must also realize that anyone taking part in a temple meal displays a relationship with that god.

Now: The time of communion is a means of worship in the whole body, wherein individuals join together to be the body at worship. We state our alliance with the Christ, our dependence upon him, and intention to continue carrying out our obligations to him (Henry).

Extra source: Cornerstone Biblical Commentary 1 Corinthians (William Baker), 2 Corinthians (Ralph Martin & Carl Toney), ed. by Philip Comfort. Carol Stream: Tyndale House Publishers, c2006.
First Corinthians by Richard B. Hayes (John Knox Press, 1997) on line athttp://books.google.com/books?id=M_PC0PAs3VYC&dq=1+Corinthians+and+Richard+B.+Hays&printsec=frontcover&source=in&hl=en&ei=2oPcStDCIIvf8Aaq0Ki3BQ&sa=X&oi=book_result&ct=result&resnum=11&ved=0CCMQ6AEwCg#v=onepage&q=1%20Corinthians%20and%20Richard%20B.%20Hays&f=falseCommentary on the Whole Bible (Acts to Revelation) by Matthew Henry, online see http://www.ccel.org/ccel/henry/mhc6.iCor.xi.html