As a child of God, you are expected to represent the truth of human existence. If someone knows you are a Christian, anything you do, they will think all Christians do. If they do not know you are a Christian, and they know enough about Christ, they will see how you conduct yourself and say you must (or must not) be a Christian. A light illuminates its surroundings. A light can also indicate the state of things. A light can communicate. All the things that light can be, Christ says you are.
Matthew 5:13–16; 1 John 3:1–3; John 1:5–14; Philippians 2:12-18
