The church as the goal or the instrument of mission?

In "Salvation to the Ends of the Earth", I can't figure out where Kostenberger and O'Brien stand.
On the one hand, they say this
"The apostle understood his ministry within the context of an Old Testament expectation in which the nations would on the final day partake in God's ultimate blessings to Israel. Paul knew that he was entrusted with God's 'mystery', the eschatological revelation that now Jews and Gentiles alike were gathered into one body, the church"
pp 258
On this reading, the church, and the churches seem to be a fairly important part of Paul's message. The new community is not simply incidental, but the goal of the preaching.

But then, after discussing evangelism they say
"But he also founded churches as a necessary element in his missionary task" pp259
It would be easy to misread K+O'B here and see the churches merely as instrumental to the mission to individuals. But it is clear here that Paul's task of calling the Gentiles to the obedience that comes from faith necessarily involves them in a new community. It is the new community that is paraded before the powers and authorities, it is the new community that is presented up to God as a pleasing sacrifice.
The church is not simply the instrument of mission, but its goal.