According to what I understand it was the custom for the Jewish bridegroom to pick up the bride to be and they walked to the grooms fathers house where the marriage takes place. All the virgins had oil in their lamps. Some believe the parable is saying they had empty lamps. The difference was that the wise took a back up supply of oil to refill if the bridegroom tarried! When he did not come as soon as the foolish five thought he would they were unprepared! There "oil" or fire had ran out! Then they begged for oil from the wise! I believe the "oil" represents faith, perservance, be on fire for the Lord etc. This is the responsibility of each one of us as it can not be loaned or borrowed! We can not put a time table on the Lords return so we must always be prepared no matter the hour he returns! We do not want to be on the outside and hear "I do not know you"