Now, brothers and sisters, about times and dates we do not need to write to you, 2 for you know very well that the day of the Lord will come like a thief in the night. 3 While people are saying, “Peace and safety,” destruction will come on them suddenly, as labor pains on a pregnant woman, and they will not escape.
4 But you, brothers and sisters, are not in darkness so that this day should surprise you like a thief. 5 You are all children of the light and children of the day. We do not belong to the night or to the darkness. 6 So then, let us not be like others, who are asleep, but let us be awake and sober. 7 For those who sleep, sleep at night, and those who get drunk, get drunk at night. 8 But since we belong to the day, let us be sober, putting on faith and love as a breastplate, and the hope of salvation as a helmet. 9 For God did not appoint us to suffer wrath but to receive salvation through our Lord Jesus Christ. 10 He died for us so that, whether we are awake or asleep, we may live together with him. 11 Therefore encourage one another and build each other up, just as in fact you are doing.
1 Thessalonians 5:1-11 (NIV)