1 Corinthians 3:8

Now he that planteth and he that watereth are one: and every man shall receive his own reward according to his own labour (KJV)

Then: The thought of the one who waters and the one who plants as being one entity matches the teachings of Christ that his followers be unified. Paul says it is a truth for he and Apollos. Even though, in the final judgement each shall receive a reward for the work which they did individually, that doesn't matter as far as the goal of serving Christ and bringing others into the kingdom is concerned. The natural man may respond well to incentives of competition, but the spiritual man responds more valiantly to the goal of not disappointing the Lord.

Now: Two other interesting parts of the rhetorical method were the incorporation of both antithetical and balanced phrases (Collins, p. 141). Verse 8, here shows one that is balanced: "he that planteth" and "he that watereth." Using them organizes thoughts in listeners' minds. When you remember one, you remember the other. Other commentators look at the broad reaching effect of these verses. Hays (p. 49) deals with the elitism which has crept into the churches - especially noticeable in the competitions between large and small ones. It takes conscious effort for believers to speak glowingly of the work in both, never intimating that that which is done in one has less eternal value than the work in another. This does not preclude the need for both small and large churches to be ever searching for better methods of cultivation. The work of a large church may be shallow and short range, while the work of a small church may be too narrow in focus.

Extra Source: First Corinthians by Raymond F. Collins and Daniel J. Harrington (Collegeville MN: Liturgical Press, c1999) online at http://books.google.com/books?id=c4VXq9fKoRwC&dq=Sacra+Pagina+and+1st+Corinthians&printsec=frontcover&source=in&hl=en&ei=NqEJS7XzEITklAeejdiEBA&sa=X&oi=book_result&ct=result&resnum=11&ved=0CDUQ6AEwCg#v=onepage&q=&f=false
First Corinthians by Richard B. Hayes (John Knox Press, 1997) on line at http://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=false