The Scriptures command us to watch. They also show us that this lukewarm, latter day generation we are now in, would be going about business as usual. They would be slumbering regarding the return of Jesus. Many would not be expecting or watching for His soon return.
As the days of Noah were, the days that were before the flood, people were going about business as usual. They were not looking for or expecting the flood to come. It came and took them by surprise—they all perished. So shall also the coming of the Son of man be-ref Mt 24:38,39. WATCH THEREFORE-Mt 24:42. If therefore thou shalt not watch, I will come on thee like a thief, and thou shalt not know what hour I will come-ref Rev 3:3.
Take heed, lest Jesus comes and finds you unprepared and not expecting His return-ref Lk 21:34. WATCH, lest Jesus comes suddenly and finds you sleeping-ref Mk 13:35,36. It is written of this lukewarm generation: They all slumbered and slept-ref Rev 3:16; Mt 25:5. But we are told by God's Word: LET US NOT SLEEP, as do others; but LET US WATCH and be sober-ref 1 Thes 5:6.
BLESSED ARE THOSE "SERVANTS" whom the Lord when He cometh shall find WATCHING-Lk 12:37. UNTO "THEM" that LOOK FOR HIM shall He appear the second time without sin unto salvation-Heb 9:28.