Marriage Process
The marriage process in ancient Israel went like this:
The agreement A man went to the girl's father's house and set up an agreement. Then they put the agreement in writing
The bride price The man paid the bride price to the father. Technically, this gift belonged to the bride and it set her free from her parents. Once the bride price was paid, the woman belonged to the man and was (in the eyes of the community and law) legally married
The betrothal period At this point, the groom returned home without his bride. Even though they were legally married, they could not be together for a year and did not have sex.
The wedding After a year, the man came to the town, bringing his family and party to "carry away" the woman and take her to the wedding party. At this point in the wedding process, the groom took her from the house to the wedding site where they partied (from four to seven days, usually).
It is claimed that the groom would often show up at a random time to surprise his bride (occasionally in the middle of the night). It is also claimed that the groom could call the wedding off before the feast and turn her away.
Source (this is one source among many).
Ten Virgins: Ten Brides
If we put the Parable of the Ten Virgins in context of this ancient wedding traditions, we can see that the point-in-process that Jesus refers to is the betrothal and wedding process.
The bridegroom is coming take take away his wife for the wedding party. The bride price has been paid and the betrothal period has passed. The virgins knew that the bridegroom was approaching, but they didn't know when he would come exactly.
Because of all these contextual clues that Jesus gave us in the parable, we can easily conclude that the ten virgins were actually all brides of the bridegroom, not just the wedding party.
If we put this in context, the parents of the bride were not required to remain vigilant. Nor were the servants of the house. Nor were any brothers who were also living in the same household. These were, after all, virgins. Even a loose translation of the word, parthenos, gives us "young girls" (from the definition "one's marriageable daughter").
Clearly, the groom is coming for the bride. In this case, he has ten brides that he is coming for. And he's coming to carry off the bride(s) in the middle of the night (which, apparently, was not unheard of).
Historical Polygamy
To help further support this idea that the groom was coming for ten brides, we can see that polygamy was actually common during the time of Jesus.
The historian Josephus had twice noted that polygamy was permitted to Herod because it was permitted by Jewish custom. This actually went against the Roman laws that forbade multiple wives (which is what made the multiple marriages allowed to Herod notable to Josephus).
Ten Virgins: Symbology
The ten virgins in this parable clearly refer to the church members. Directly before this parable, Jesus tells his disciples to be prepared for his second coming:
Matthew 24:42-44 (NASB)Emphasis added
42 “Therefore be on the alert, for you do not know which day your Lord is coming. 43 But be sure of this, that if the head of the house had known at what time of the night the thief was coming, he would have been on the alert and would not have allowed his house to be broken into. 44 For this reason you also must be ready; for the Son of Man is coming at an hour when you do not think He will."
He adds to his warning by including the "thief in the night" parable showing that Jesus will return suddenly and unexpectedly. We, therefore, as his chosen people must be ready for his coming.
In the parable, there are ten virgins; half of them are prepared and the other half are not. The half that are ready are taken away to the marriage feast as the bride--they join to the groom in marriage. The other half are not.
In context of the previous warning of Jesus, it is very clear that the ten virgins are symbolic of the church. It also serves as a warning to be ready and sanctify yourself (as a betrothal period). We are no longer under the law; the bride price has been paid and we are now married to Jesus. We're just awaiting his coming!
Ten Virgins: Bridesmaids?
Some have claimed that the ten virgins are bridesmaids. However, this interpretation fails in many senses.
First, in the marriage traditions of the day, the groom did not come to carry away the servants of the bride, but the bride herself. The interpretation of the virgins as bridesmaids fails the historical context.
Also, Jesus is coming to take us away from this world for a place he is preparing for us. In this parable (and per the traditions), the groom is coming to take away the brides. His goal in showing up is not to take away the bridesmaids only to return them later.
Further down this road: If this parable were to be interpreted as bridesmaids, they would be returned to the house of their father after the wedding: only the bride is taken with the groom. If this were the interpretation, the groom (Jesus) would end up leaving his church (the "bridesmaids") behind after the feast was over.
Because of this, the interpretation falls short on the eschatology. Clearly Jesus is coming to take us away, not just "borrow us" for a short while.
Another point, the servants of the brides would not be referred to as "virgins", but as "servants". We can see this clearly from the wedding in Canaan, the site of Jesus' first miracle. If these were "bridesmaids", they wouldn't be referred to as "virgins".
Another possibility is that they would be referred to as maids, as is Genesis 29:24, where a maid is given as a bridal gift.
Also, putting bridesmaids into this story would be anachronistic!
The history of bridesmaids allegedly comes from an old Roman law stating that there had to be ten witnesses. Of course, the immediate assumption is that 10 witnesses = 10 virgins. However, while valid at face value, this quickly dissipates under closer examination! First and foremost, if these virgins were needed as witnesses, the groom would not throw them out of the party.
Also along these lines, while the Roman law required that there be 10 witnesses, it also prevented these witnesses from being women. In other words, while bridesmaids may have descended from the ancient Roman laws, there were no bridesmaids in the ancient Roman empire!
Finally, the idea of "bridesmaids" didn't come around until many years later. The horizon of understanding that Jesus would have had at the time of this telling would not have been of 10 virgins that needed to fulfill the law by witnessing a ceremony, but 10 people that needed to witness the ceremony in order to fulfill the law. The idea that he would have included 10 virgins in the story as the people needed to fulfill the Roman laws is ridiculous.
Therefore, since (a) the groom would not throw out the witnesses that the law required, (b) the witnesses had to be men and (c) the concept of "bridesmaids" originated from these set of male witnesses, clearly bridesmaids would have been anachronistic in the ancient Roman Empire!
Again (admittedly, probably the weakest point), the servants of the bride would not be waiting for the groom, but rather waiting for the bride to be taken away. Their focus would be on the bride and on the party, not on anxiously awaiting the groom. It seems incredibly odd to me that a bunch of servants to the bride would be waiting for the groom instead of helping the bride wait. The focus of the story seems odd and the mental leaps required to imagine that Jesus would talk about servants waiting for a bridegroom seem to be too much of a stretch.
So why this interpretation?
The reason that people interpret this as bridesmaids is to avoid the unpleasant reality of the popularity of polygamy in the days of Jesus. As we've seen earlier, however, polygamy was a custom of the time and a historical fact. Modern ethics say that polygyny is "wrong" and therefore commentaries tend to interpret things through this lens.
With the realization that polygyny was common and acceptable during that day, we can clearly see that these are brides, not servants.
Summary
The ten virgins in this parable are all, very clearly, brides of Christ.
The parable itself is a very clear eschatology reference saying that the church members (the virgins) are to remain ready and waiting for Jesus (the groom) because he will be coming soon. In fact, directly before this parable, Jesus says that he is coming very soon; that we should remain ready; and his coming will be like a thief in the night; and that he will be taking us to a new home. Given this context, the parable is clearly referring to members of the church being ready and waiting for Christ's return.