Mark 13:29-37

29 In the same way, when you see all these things happening, you are to know that the time is near, right at the door.
30 Yes! I tell you that this people will certainly not pass away before all these things happen.
31 Heaven and earth will pass away, but my words will certainly not pass away.
32 However, when that day and hour will come, no one knows -- not the angels in heaven, not the Son, just the Father.
33 Stay alert! Be on your guard! For you do not know when the time will come.
34 "It's like a man who travels away from home, puts his servants in charge, each with his own task, and tells the doorkeeper to stay alert.
35 So stay alert! for you don't know when the owner of the house will come,
36 whether it will be evening, midnight, cockcrow or morning -- you don't want him to come suddenly and find you sleeping!
37 And what I say to you, I say to everyone: stay alert!"