How far away did the prodigal son go? For the purpose of this illustration, let us say that he was living not too far away from home. He didn't travel far away, he just wanted to live outside parental authority.
A young man with a whole lot of money, who was living outside parental authority, will squander the money by all means. When you get money that is not proportional to his age and experience, you are bound to mess up. Michael Jackson and Mike Tyson are all examples of people who received too much money too early in life. If you live outside parental authority and do not take advice, death, disgrace and disease are not too far away from you.
Verse 14-15 show us that the young man squandered the money and had to work on a pig farm. This was a lifestyle that does not befit his upbringing and culture.
The prodigal son is not an alien. He is among us. A girl who has been brought up in the church and ends up as a prostitute can be likened to the prodigal son working on a pig farm.
The young man, despite all this freedom, missed something- decency and discipline. This pushed him to go back to his father. His actions showed his intention of returning to his father. While he was still a far way off, even before he spoke, his father threw his arms around him.