"Way Maker" by Leeland (and performed by Passion, Kari Jobe, Josh Baldwin, Krisitan Stanfill, and others) is a popular worship song built around a 4 chord progression that repeats throughout the entire song. As you begin to learn Nashville Numbers, you can see why this particular pattern (4, 1, 5, 6m) works especially well for a progression that is repeated often. Because the 1 is always in the middle of the progression, it never resolves. It is a continuous "open loop," which makes room for a melody to be repeated over top. Check out the charts and see for yourself!