In the first 10 verses of 1 Corinthians Chapter 3, Paul focuses on the divisiveness of the church at Corinth and exhorts the believers to learn to work together for the accomplishment of God’s mission. 1 Corinthians 3:9 says that 
we indeed are co-workers and we’re all working in the field, but the field is God’s field, not our own. Paul wants the church to grasp the synergistic relation of the different apostolic workers. They share the burden and Paul invites the various members of the church to join in the calling to work together for the common goal of making disciples. What matters, looking back at Jesus’ use of the vine and branches analogy, is the fruitful cultivation of the harvest. Paul wants them, as he and Apollos and Cephus have done, to set aside their individual preferences to form a more cohesive union towards the accomplishment of God’s mission.
I like what Hays says in commentary, “It is easy to give lip service to this principle, but hard to live out its practical implications in the church.” It’s so easy for us to become embroiled in turf wars instead of working cooperatively to cultivate God’s field. When that happens the field becomes endlessly subdivided into unproductive isolated efforts with each part doing its own thing. The role of individuals is not nearly as important as the participation of each part of the body. When we all focus on watching out that no one else interferes with our little patch of the field, it destroys the overall effort. As Hays continues, he says that Paul is saying to his readers, then and now, “No, don’t you understand that the whole field belongs to God and that we are called to work together to bring in the eschatological harvest? Individual leaders are insignificant; they are just field hands.” We are all just field hands.
While in Israel we visited the Church of the Holy Sepulchre in Jerusalem. There’s probably no better example (except maybe the 1st century church at Corinth) of the foolishness of turf wars and bitter jealousies. The Church of the Holy Sepulchre is built on one of the two suggested sights for the burial of Jesus. Although the garden tomb seems to be the more likely place, tradition has supported the Church. Today this church is divided up into different sections under the jurisdictions of the different Christian groups that want to claim a piece of the purportedly holy place: Greek Orthodox, Armenian Orthodox, Roman Catholic, Ethiopian Orthodox, and so forth. Jesus came to break down barriers that divide people, not to create them.