The churches in the province of Asia send you greetings. Aquila and Prisca greet you warmly in the Lord, and so does the church that meets at their house.
There's a building on most high streets with a noticeboard out front and service times in neat letters, and for plenty of people that's what the word church means. If you're curious about faith but have only ever seen it from the pavement, that's a fair assumption to make. Church, as far as anyone can tell from outside, happens in that room, at that hour, once a week.