Matthew 25:1-13:

"Then the Kingdom of Heaven will be like ten bridesmaids who took their lamps and went to meet the bridegroom.  Five of them were foolish, and five were wise.  The five who were foolish didn't take enough olive oil for their lamps, but the other five were wise enough to take along extra oil.  When the bridegroom was delayed, they all became drowsy and fall asleep.
At midnight they were roused by the shout, 'Look, the bridegroom is coming! Come out and meet him!'
All the bridesmaids got up and prepared their lamps.  Then the five foolish ones asked the others, 'Please give us some of your oil because our lamps are going out.'
But the others replied, 'We don't have enough for all of us.  Go to a shop and buy some for yourselves.'
But while they were gone to buy oil, the bridegroom came.  Then those who were ready went in with him to the marriage feast, and the door was locked.  Later, when the other five bridesmaids returned, they stood outside calling, 'Lord! Lord! Open the door for us!'
But he called back, 'Believe me, I don't know you!'
"So you, too, must keep watch! For you do not know the day or hour of my return."