The Gospel at Mass finds Jesus telling his disciples to be prepared for the coming of God.
From the Gospel of Matthew Chapter 24:
Jesus said to his disciples:
“As it was in the days of Noah, so it will be at the coming of the Son of Man.
"In those days before the flood, they were eating and drinking, marrying and giving in marriage, up to the day that Noah entered the ark. They did not know until the flood came and carried them all away.
"So will it be also at the coming of the Son of Man. Two men will be out in the field; one will be taken, and one will be left. Two women will be grinding at the mill; one will be taken, and one will be left. Therefore, stay awake!
"For you do not know on which day your Lord will come. Be sure of this: if the master of the househad known the hour of night when the thief was coming, he would have stayed awake and not let his house be broken into. So too, you also must be prepared, for at an hour you do not expect, the Son of Man will come.”