The Bible commands us to be sober, and that word is used to mean that we should not get excited about the things of this world, but rather that we should live a life knowing that the coming of the Lord is near and this should not come as a surprise for us as for those who do not know him.
But let us, who are of the day, be sober, putting on the breastplate of faith and love; and for an helmet, the hope of salvation.
1 Thessalonians 5:8 (KJV)
Paul, in Thessalonians chapter 5 spoke of the “day of the Lord”, making them understand that on that great day Jesus will come as a thief in the night, however, this simply for the children of darkness, since we, who are of the day, it should not surprise us as a thief in the night.