1 Thessalonians 5:3-6

When they are saying, Peace and safety, then sudden destruction cometh upon them, as travail upon a woman with child; and they shall in no wise escape. But ye, brethren, are not in darkness, that that day should overtake you as a thief: for ye are all sons of light, and sons of the day: we are not of the night, nor of darkness; so then let us not sleep, as do the rest, but let us watch and be sober.