I Thessalonians 5:4-6, 8

But you, brethren, are not in darkness, so that this Day should overtake you as a thief. You are all sons of light and sons of the day. We are not of the night nor of darkness. Therefore let us not sleep, as others do, but let us watch and be sober.

But let us who are of the day be sober, putting on the breastplate of faith and love, and as a helmet the hope of salvation.