1.  Believers are changed people, we once lived in darkness, now we live in the light.  We are children of light and must therefore live “true to our place in God’s family.”

2.  The contrast between light and darkness is a common Biblical theme:  we must put aside the deeds of darkness, and put on the armor of light (Romans 13:12); we must not be yoked with unbelievers since light can have no fellowship with darkness (2 Corinthians 6:14); we are sons of the light and of the day and do not belong to darkness or the night, thus we must be alert and self-controlled (1 Thessalonians 5:5); we can’t claim to have fellowship with God and walk in the darkness (1 John 1:5-7).

3.  When one walks in the light, their life is characterized by goodness (“generosity of spirit,” ”love in action”), righteousness (“right character before God and right actions before men”); and truth (truth lived out, “conformity to the Word and will of God”).  (Quotations by William Barclay and Warren Wiersbe)

4.  As believers walk in the light they expose (or reprove) those living in darkness (carnal Christians and non-Christians alike).  J. Vernon McGee express well the intent of this passage: “This does not mean that the believer is to become a reformer.  It does mean that by the light of his life he is a rebuke to the works of darkness.  Darkness is not driven away by preaching at it; darkness is dissipated by the presence of light.”