Parable of the Ten Virgins
In order that people would always be ready to meet the Lord, the judgement of God, which means to be ready for death since death is the beginning of the judgement of God over men, Jesus Christ told the parable of the ten virgins. In this parable, the Lord likens us to virgins who had gathered for a marriage. According to Eastern wedding customs, the groom went for his bride, who awaited him in the home of her father. Her friends, virgins, had to meet the groom with burning lanterns in late evening, and accompany him to the fiancée.
Then, the Kingdom of Heaven shall be compared to ten virgins, said the Saviour, who took their lamps and went to meet the bridegroom. Five of them were foolish, and five were wise. For when the foolish took their lamps, they took no oil with them; but the wise took flasks of oil with their lamps. As the bridegroom was delayed, they all slumbered and slept. But at midnight there was a cry, "Behold, the bridegroom! Come out to meet him." Then, all those virgins rose and trimmed their lamps. And the foolish said to the wise, "Give us some of your oil, for our lamps are going out." But the wise replied, "Perhaps there will not be enough for us and for you; go rather to the dealers and buy for yourselves." And while they went to buy, the bridegroom came, and those who were ready went in with him to the marriage feast, and the door was shut.
Afterward the other virgins came also, saying, "Lord, lord, open to us."
But he replied, "Truly, I say to you, I do not know you." After finishing this parable, the Saviour said, "Watch therefore (always be prepared), for you know neither the day nor the hour in which comes the Son of man."
The "foolish virgins" correspond to those careless people who know that they have to appear at the judgement of God but who do not prepare themselves for it while they are alive on earth, while death has not overtaken them. They do not repent of their sins and do not do good deeds. The "oil in the lamps" means good deeds, especially works of mercy. The "sleep of the virgins" represents the death of people.
Our Judge ("The Bridegroom"), Jesus Christ, will come to earth and all the dead will awaken from the sleep of death, that is, they will be resurrected. As death finds one, prepared or unprepared for the judgement of God, so he has to appear before the judgement of God. Then, careless people will not be able to look for help from anywhere, and they will hear from Christ the bitter words, "I do not know you; depart from Me."
Note: See the Gospel of Matthew 25:1-13.