This truth is incredibly simple, yet overwhelmingly profound. In Jesus’ analogy, there are those who are in the light and those who are in the dark. Jesus explained the difference between the two in John 8:12, when he said, “I am the light of the world: he that followeth me shall not walk in darkness, but shall have the light of life.” Those who are true followers of Jesus are those who are in the light, but those who do not follow Jesus, are those who are kept in darkness.
This darkness is a two-fold darkness. In his analysis on 1 Thessalonians 5, John Macarthur teaches of this two-fold darkness with the following two categories,
“…one is mental darkness, the other is moral darkness. The darkness of ignorance, on the one hand, the darkness of sin on the other. The darkness of unbelief on the one hand, the darkness of rebellion on the other. One is the darkness of not knowing, the other is the darkness of not doing...not knowing what is true, not doing what is right. The heart of an unregenerate, unsaved person is dark. That which generates his conduct is dark and so his conduct reflects the darkness.”
As Paul continues his letter to the Thessalonians in chapter 5, he addresses them based upon their nature as children of light. No longer are they to pursue the sinful lifestyle of darkness, but rather, knowing of the return of Jesus, they should be living lives that would exemplify their new nature. They are not in the dark regarding the return of Jesus, nor are they in the dark regarding the desires of God. Through the teaching of God’s word and the work of the Holy Spirit, they have been drawn into truth and should live in such a way that would reflect that.
Food for Thought: If you claim to be a believer, your life should indicate it. What are a few of the things that Paul mentions in vss. 4-11 that would indicate that you are no longer in darkness?