If writers want to gain attention with an arresting statement, he put the cuffs on me with this one. I couldn't go on without wagging my head in amazement.
Careful theologians do not build their doctrine of the church merely around the use of the word ekklesia.
The doctrine of the church is called ecclesiology after that Greek word ekklesia. By making his statement, Bauder opened up a small nation to drive through with his ecclesiology. One could get a sufficient knowledge of Scriptural teaching on the church by studying how the word "church" is used in its context. If someone wants to understand the church then he really would want to let God tell him what the church is by looking at the passages where He uses that word.
What he will find is that in a large majority of the usages of ekklesia, the Bible is referring to a particular assembly of immersed believers. In pre-NT extrabiblical literature, ekklesia is an assembly. People in that day would have understood it as an assembly. Therefore, we take the meaning of that word derived from how it was used by men contemporary with the New Testament and by the NT authors, and we build our doctrine of the church on that. Men were called out of their homes for public gathering. That meeting was an ekklesia---visible, physical, and local. Other passages which are not clearly referring to a church are interpreted in light of those texts which do mention it. We let the Bible formulate our disposition about the word.
The chapters and verses of Scripture that use "church" are about "church." The references without a mention of "church" do not guide those which do have the term. In the next two sentences of his essay, Bauder writes:
The New Testament uses many images or word pictures to reveal truth about the church. One of the most instructive is the image of the flock, found in John 10. It occurs in one of the few parables in John’s gospel.
John 10 doesn't have the word "church." To start, one can only determine that "flock" of chapter ten of John is "church" by means of speculation. We shouldn't speculate to get our doctrine. Doctrine based on speculation is at best Speculative Theology, not even a close relative of Biblical or Systematic Theology. Bauder isn't being a careful theologian when he bases a doctrine on his own speculation, even if he is president of a seminary.
Beginning with a predisposition based upon what the Bible actually says about "church," one reads John 10. A church is made up of immersed believers (Acts 2:41). The "flock" and "fold" of chapter ten of John relate to salvation (John 10:8, "he shall be saved"). John 10 is a soteriological passage, not an ecclesiological one. Jesus' sheep are secure in His fold (John 10:28, 29). A church member can be loosed from the assembly (Matthew 18:15-18). If the church is a fold, then there is a contradiction between John 10 and Matthew 18. Water baptism is not a requirement for entrance into the "fold," but it is for the "church" (besides Acts 2:41, also consider 1 Corinthians 12:13). At the most, John 10 shows how that future members of the church are converted---through Christ alone. We conclude that a careful theologian will not include John 10 into his ecclesiology.
Why does Dr. Bauder bring the church into John 10? That view supports his predisposition about the church, which doesn't come from passages with the word ekklesia, but from theologies written by reformed Catholics. John 10 isn't ecclesiological. When someone makes salvation the entrance into the church by reading in his own opinion into John 10, he isn't doing careful exegesis. He's only giving you uninformed speculation.