5 You are all sons of light and sons of the day. We are not of the night nor of darkness. 6 Therefore let us not sleep, as others do, but let us watch and be sober. 7 For those who sleep, sleep at night, and those who get drunk are drunk at night. (1 Thessalonians 5:5–7, NKJV)
The return of the Lord will not overtake Christians suddenly and unexpectedly, because we “are not in darkness” (1 Thess. 5:4). Paul uses light and day to describe the moral readiness of Christians concerning the coming of Jesus. What does it mean to be “sons of light” and “sons of the day?” The gospel called us out of sin’s darkness (1 Pet. 2:11). By the redemption we have in Christ we have been delivered from the power of darkness and conveyed into the Son’s kingdom (Col. 1:13). We used to live in the darkness of sin, “but now you are light in the Lord. Walk as children of light” (Eph. 5:8). Darkness and night describe the moral slumber of living in sin. Just as we are unaware of our surroundings in sleep, the darkness of night gives cover to sin and its excesses. We must refuse to be lulled to sleep by the enticements of sin. Let us live vigilantly in truth and righteousness, abstaining from everything that intoxicates the mind and soul. Sons of light are sober, diligently living with self-control and not indulging the flesh with sin. That is why sons of light are ready for the Lord’s return. Walk in the light of truth, not in the darkness of sin (1 Jno. 1:5-10). Be ready of His return.