Any organization that is going to be successful has to have one thing; unity.  They have to be united in their purpose, their direction, and the means by which they are going to achieve their common goals.  If they don't have unity, the rest is irrelevant. 

The church is no different.  In 1 Corinthians 3:1-9, Paul addresses one more area of agreement that the church must come to in order to successfully fulfill God's commission for them; unity in our understanding of spiritual maturity.