Why should evangelicals care about something as arcane as the ontology of the church?
Evangelicals traditionally have been noted for their concern for the ontology of the person. They preach the gospel with the view to getting the individual transformed or "born again." Persons are spiritual entities who, because of sin, need to experience the miracle of conversion. Unfortunately, they have not extended this understanding to the church. They fail to see that conversion is not about transforming the individual, per se, but is incorporation into a spiritual realitythe Body of Christ. Another way of putting it is to say that the church is more than the sum of the individual membersprecisely because of her relation to Christ and the presence of the Spirit. Evangelicals' failure to understand this fact has led to their seeing the church as essentially a collectivity of our own making. Church is only a practical way of organizing individual Christians for effective ministry.
Certain consequences follow from such a view of the church. For example, evangelistic outreach to and formation of individuals becomes the paramount concern of the church. But if the church herself is more than an entity of our own making, then different consequences follow. The church will still be concerned about outreach and formation of people, but the overarching reason for being will be defined by her relationship to God. Her response to the revelation of God in worship becomes paramount.
Concern for the redemption of the world has been an evangelical hallmark ("God so loved the world " [Jn. 3:16] our favorite verse begins). Yet you argue that God's purpose is less about the redemption of the world and more about the election of the church. ...