Pastor Trevor uses the tuning of a guitar and a radio as a way of seeing our need to "tune our hearts to sing God's Grace," to quote the old hymn, "Come Thou Fount." To tune a guitar, you need either to tune to something which is "perfect" in pitch, like a digital tuner. The "tuner" of the Christian life is God's written Word, the Bible. Regular reading of Scripture is the best way for us to "tune" our lives to God's mercy and grace. A second way to tune a guitar, which is not perfect but still helpful, is to tune to another instrument. In our analogy, we can start to tune our lives to God by listening to the worship of others (music and preaching). Since God's glory is continuously streaming and transmitting (Ps. 19:1-3), our lives are meant to repeat and amplify that glory in actions and words which our world can see and comprehend!