The tree-like functions of the church

Just as an oak tree begins as an acorn and grows, soaking up the sun and rain, so that it can branch out and produce more acorns that will grow into acorn-producing trees, our church exists to perpetuate itself. Since the founding generation of apostles, the church has evangelized and taught and fellowshipped and encouraged to make more Christians and more churches.
Each disciple is involved in the work of the ministry- making more disciples that will, as part of their discipleship, make more disciple/dicsiple-makers.

The self-perpetuation, though, is not the actual purpose of the church. While the tree has sprouted and shot up throughout the centuries, each inch of growth, each piece of fruit is a sweet aroma to God. That there is a church that exists to display Christ to the world is the purpose, not how it keeps going.