Passing Thoughts

In working with and around a lot of Evangelicals, I hear the term "Bible-based" church thrown around a lot. However, since the Bible didn't actually come into existence until the latter part of the fourth century, would today's Evangelical or Fundamentalist consider third through fourth century Christians to have been part of a "Bible-based" church? And what exactly are the standards for being a Bible-based church, and who authoritatively enforces them?