1) We read in the Gospel of Mathew, chapter 24:
27 For as the lightning comes from the east and flashes as far as the west, so will be the coming of the Son of Man.
30 … and they will see “the Son of Man coming on the clouds of heaven” with power and great glory.
31 And he will send out his angels with a loud trumpet call, and they will gather his elect …
2) And it is written in the Gospel of Luke, chapter 12:
35 Be dressed for action and have your lamps lit;
36 be like those who are waiting for their master, so that they may open the door for him as soon as he comes and knocks.