Revelation 1:20 explains that churches are (seven) lampstands in the vision shown to John. In verse 4:5, the Spirit of God is referred to as a lamp (or seven lamps). This juxtaposition means two things to me. First, there's a Spirit for each church. Not literally, of course, but that the Spirit is fully available and present for every church. Second, we are not the light of the world by ourselves. We are given the privilege of holding the Light for all to see.
Jesus, help me to hold your Light high, that when others look at my stand, they'll see You shining brightly.