“If you look at the three verses following the “Thief in the night” verse, it’s easy to see Paul, under the inspiration of the Holy Spirit, is comparing non-believers and believers. The Lord will come like a “Thief in the Night” to the world and non-believers. But notice, for those who are His, they are “not in the darkness that that day should overtake you as a thief.” In other words, believers will not be surprised by His coming in a broad sense, and they should be looking for it.”