The powerful imagery of light and darkness is a common one in both the Old and the New Testaments for illustrating the differences between Christians and unbelievers.
Paul does not view either of these states as static. His readers once had not only been influenced by darkness but were also extenders of darkness. The features of spiritual darkness include ignorance of God, of the gospel, and of grace. Similarly, when he describes the Christians as ‘light in the Lord’, he means that in addition to being recipients of light they are givers of light.
Paul highlights three features of light that will be transmitted by believers: goodness, righteousness and truth. These details are the result of the shining presence of the Spirit of life in their hearts. Perhaps Paul is using the well-known fact that a tree only bears fruit because there is light.
How do believers become light-projectors? It is by being light-receivers in the sense that they receive from Christ through using the various means of grace. They are given light through meditation on the Bible, through answered prayers, through fellowship with God’s people.
In verses 11-14 Paul deals with the witness of the children of light to the world. He says there is a threefold approach: reproving, revealing and resurrecting – and they represent a threefold strategy for Christian witness.
When Paul tells his readers to reprove sinners, he does not mean ‘in the sense of admonishing or rebuking. It means to convince by evidence’ (Charles Hodge). It is not enough to say to a person that their conduct is wrong; they must be shown why it is wrong.
Paul describes the effect of such reproving. When unbelievers have such an encounter with a Christian, it is for them an encounter with light. Just as light shines in a dark room, so the words of a consistent Christian shine in the minds and consciences of non-Christians. They begin to see the nature of their sin and the mercy of God. In a sense, meeting such a Christian is like meeting with Jesus.
This leads on to the third stage, that of resurrection, described in verse 14. This is a description of a command to an unbeliever to arouse himself and come to Christ. The change is likened to a resurrection, which it is. The person who is in the state of spiritual death becomes alive.
As we think of our interaction with the world, several ideas come to mind. First, there is the need for carefulness in how we live. We are to make sure that there are no dark spots spoiling the shining of our light.
Second, there is the necessity of compassion in the way we point out people’s sins to them. We don’t approach them as judges but as those who once were sinners, who once were also in darkness.
Third, there is the possibility of confidence that the Lord can use us a means of bringing others to himself. This threefold strategy is not our method, but his. When we speak as children of light, we spotlight the darkness around us, in other people and in the world.