Beyond illustrating the opportunity of repentance and reclamation for the straying wasteful (prodigal) son/daughter, this parable illustrates the nature and attributes of God. First, no parable may be taken literally--which means according to the strict meanings of the words--because a parable is a brief story told using that which is familiar to explain religious and spiritual ideas that are complex and unfamiliar.

As T. K. Hardison M.Th. says, Jesus told parables so that even children could understand the complex truths about the nature of God and the Kingdom of God. According to Hardison, one thing this parable shows, in a fashion even children can understand, is that God takes an active role in pursuing the repentance and reclamation of humanity: the father ran to meet the returning son, just as the shepherd went out searching high and low for a lost lamb.

While no parable may be taken literally according to its strict meaning, parables explain and illustrate deep truths in simple understandable ways, truths such as the attributes of God. So, no, we don't take this parable or any other literally. But, yes, this parable and all Jesus' parables communicate truth, even though through the fiction of brief stories.

Just to add to #2, I think if you read the first two verses of Luke Chapter 15 it is absolutely clear that Jesus was telling this very pointed parable to an audience consisting of the "sinners" (tax collectors etc) and "the righteous" of the day. What is important to remember about parables is that they are often prompted by something that is said or done or an attitude, and are used by Jesus to correct and teach. Given the Pharisees' complete lack of understanding about Jesus and his eating with "sinners", Jesus tells this parable to tell them the truth about God's love, but also crucially to show them that they need to return to the Father just as much as the "sinners" do. What is vital to realise in this parable is that the younger son does return to the father. The elder son is left in the fields at the end of the story - will he return to the father's household and join in the feast, or will he stay out in the cold? What is so masterful about this parable is that it challenges and invites a response from the Pharisees - which their subsequent actions clearly show. Jesus is using fiction here to make a far more effective point, message and challenge than if he had challenged the Pharisees openly.

On a more general note, Jesus used parables often in his teaching.  Parables are stories used to make a point or to teach, as has been so ably discussed above.  They're fiction, and they serve to make a point about some principle or belief without placing guilt or blame on anyone specifically. They allow us opportunity to reflect. That's one of the great things about fiction--it allows people to view their flaws in others without the harsh sting of recrimination or scolding.  The concept of a parable is to allow listeners or readers to make personal application without feeling they've been personally condemned.  Jesus told stories because they're interesting, accessible, and thought-provoking--as well as effective.   

While I agree with the two posts above (they have done a wonderful job of explaining this parable and what a parable's purpose is), I would also like to point out that this work of fiction which was told to explain God's belief system toward the people on this earth, should also be taken literally.  Although the Prodigal Son did not exist, and his story was told as an illustration--the Son representing sinners everywhere--God is the Father in the story.  He wants us to be independent, but He also wants us to return to Him when we have gone astray. Nothing we do is so bad that God can not forgive as long as our prayers are sincere and our actions show that sincerity.  Satan is the one who works on us to tell us we are not worthy and that we might as well "enjoy" life since God will never have us back.  Satan is the one who plants the seeds of jealousy, unrest, hatred, greed, revenge, excessive pride, power, superiority, lust, etc.   Sinners are always welcome back to the fold, and those of us who stay on the path (as the other son did) are responsible for guiding those who have strayed back home--without malice, jealousy, or envy.  The prophet John states clearly in Revelation that God is waiting to send His Son Jesus Christ back to Earth in order to give time enough for all of us to be saved.  He is patient in that manner...He is waiting for all the Prodigal Sons to come home from a wayward life of sinning through selfishness, attraction to what looks great but that does not offer salvation or redemption...nothing on Earth can fulfill one's soul more completely than the love of God.

The previous post was really quite stellar.  I think that you probably got much of what was needed through the lucidity offered.  I would like to delve into the idea of literal interpretation.  You raise a very powerful point in the secondary nature of the question.  I think that religious interpretation in strict or symbolic senses is really part of the essence of spiritual and religious worship.  It is difficult to read as to what is "the right way" to pursue on this.  There are many who believe that a religious text, whatever it may be, has to be take in absolutist and literal terms.  They believe that "truth" is only to be conveyed through a strict and orthodox adherence to what is presented in religious scripture.  There are others who argue that the religious text is a guide, a symbolic light for us to follow.  Its exact details are important, but the overall message for us to follow is where its "truth" lies.  I think you can also find other lines of logic that argue individuals having the power to decide what they find as truth bearing symbolic elements and literal components, using each to carve their own path to divine providence.  In the end, I think that this is one of the largest issues present in religious worship.  You raise it and it is one that has been present for oceans of time in religion.  It's so interesting to see how a random question posted on Thursday, August 5 at 12:20 AM can have connections to thousands of years and eras of spiritual devotion.  I can only extend my kudos to you for such a feat.

First of all, a parable is, by definition, fictitious. For, it is defined as a narrative that illustrates a moral or religious lesson.  Differing from a fable that can employ humans, animals, even inanimate objects a parable always uses human subjects.

The Parable of the Prodigal Son, Luke 15:11-32, describes a son who returns after having squandered all his inheritance and cut all ties with his family. When the father sees him up the road as the young man is returning to beg for some type of a job in order to sustain himself, the father rejoices and has a celebration for him.  The dutiful son returns from the fields and asks his father that he was never given a goat for a feast with his friends after having worked all these years for his father.  To this the father replies,

You are always with me, and everything I have is yours.  But...this brother of yours was ...lost and now he is found.

Of course, the moral of this parable is that any sinner should return "home" and confess his/her sins, for the mercy of God is boundless.  He refuses to limit His grace.  Because the father does not abide by the old laws, the dutiful son may represent the Pharisees who often criticized Jesus.

Indeed, there is truth in fiction; often there is more truth, a greater and more universal truth, in fiction than in nonfiction.   Parables such as the one about the Prodigal Son make quick, effective lessons out of short passages, whereas a true account may make the telling too long to be effective.