Did the church fathers or OT talk about the visible and invisible church?

In the Reformation, the doctrine of the distinction between the *visible* and *invisible* church was important in the Reformers' claim not to have started a rogue church. I am wondering... + Given that it was common for the Reformers to use the Patristics, did they reference any of the early church fathers on this question? More generally, did the early church fathers speak on it? + How did they relate this doctrine to the concept of the [remnant](http://bible.cc/search.php?q=remnant) in the Old Testament? (I'm looking for actual quotes from church fathers, Reformers, confessional documents, etc.)