The Parable of the Ten Virgins.

Then shall the Kingdom of Heaven be likened unto ten virgins, who took their lamps, and went forth to meet the bridegroom? Now five of them were wise, but the other five were foolish. They that were foolish took their lamps, but took no oil with them: But the wise took oil in their vessels with their lamps.

While the bridegroom tarried, they all slumbered and slept. And at midnight there was a cry made, Behold, the bridegroom comes; go you out to meet Him. Then all those virgins arose and trimmed their lamps. Now the foolish virgins said unto the wise, Give us of your oil; for our lamps are gone out. But the wise answered, saying, Not so; lest there will not be enough for us and for you: but go you rather to them that sell, and buy for yourselves.

And while they went to buy, the bridegroom came; and they that were ready went in with Him to the marriage: and the door was shut. Afterwards came also the other virgins, saying, Lord, Lord, open to us. But He answered and said, Verily I say unto you, I  do not know you. Watch therefore, for you do not know the day nor the hour wherein the Son of Man shall come. Matthew 25 vs 1-13.