Many people have been asking this question, and let me begin by saying that just because a church is not ready to be led by an eldership, this does not mean its leadership is "unbiblical." Moreover, all church members have influence, and it is not always easy to specify exactly where influence ends and biblical leadership begins.
The New Testament pictures a fellowship where all members are using their gifts to help others. There are two general classes of gift: service gifts and teaching gifts (1 Peter 4:11). The service gifts include administration, hospitality, music, encouragement, and many more. (See my book The Spirit for a more in-depth treatment of the subject of the gifts.) Teaching gifts include the five gifts of Ephesians 4:11. Since the first two, apostles and (NT) prophets are defunct, this leaves us with evangelists, teachers, and shepherds (elders).
In my opinion--and I have been teaching this for many years--a church should aim to benefit from the roles of evangelists, teachers, and elders. This is not to say that one person might not embody more than one of these functions.
So how about this for an answer: God's word paints a picture of a church led by elders, advancing the borders through the ministry of evangelists, and informed by the biblical focus of teachers. If this is too simplistic, forgive me.
For more, please see my audio series, New Testament Leadership.
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