A letter to a church is not a letter to a building, but rather, a letter to a
group of believers. Those believers comprise the body of a congregation
that is a part of the larger body of the church, which is the visible
body and representation of the Lord Jesus in the world. When that is
understood, the idea that these words can be lifted out of their context
as some type of offer to somebody that does not know Jesus becomes
an absurdity. To use common, religious terminology, these words about
standing at the door and knocking are not directed to somebody that is
not “saved.” These words of knocking are to a church.