One of the more confusing debates about the church is how we define it in terms of its catholicity, or universality. During the Reformation Protestants wanted to make a distinction about the church as God saw it and the church as we saw it. I think this was both necessary and biblical but the result has been a major misunderstanding about the church, especially among evangelical Protestants who are not rooted deeply enough in incarnation in their ecclesiology.
I once heard a friend say that no one could gather an invisible church so the idea must have very little meaning in terms of how the New Testament speaks about the church. This is true. When New Testament writers talk about the church they are almost always (but not entirely) speaking about a congregation in a locally gathered context; e.g. the church in Ephesus, the church in Rome, etc. Paul wrote letters to these churches, not for a group of invisible people that no one could recognize.
Some evangelicals so react to what they think the Catholic Church teaches about the universal church that they deny the whole notion of physicality, sacraments and visibly shared life in the Spirit. This is an unfortunate and unbiblical excess that I address in my book Your Church Is Too Small. On this week’s book video I discuss this in a simple, easy-to-follow way.