Mark 13:33-37

Jesus said to his disciples: 'Be on your guard, stay awake, because you never know when the time will come. It is like a man travelling abroad: he has gone from home, and left his servants in charge, each with his own task; and he has told the doorkeeper to stay awake. So stay awake, because you do not know when the master of the house is coming, evening, midnight, cockcrow, dawn; if he comes unexpectedly, he must not find you asleep. And what I say to you I say to all: Stay awake!'