“They key is actually that in the story of the prodigal son the son is returning. There’s no indication of return, for any reason, in this situation and in many in which the parable is invoked.
“Jesus could have told a parable in which the father went and ran after the prodigal son’s party set shouting, ‘Hey guys! Hey guys! Can I come too? I’m a cool guy too!’ and imagined that perhaps by coming along he would evangelize the party-ers — using words only if necessary (to paraphrase the famous yet bogus St. Francis quote.) He could have told a parable in which the son comes back, unrepentant, and offers to throw a party at the father’s house, making the father an honorary master of ceremonies. He could have told a parable in which the son comes back, the father rushes out to meet him, but the son turns out to only be returning to wash his laundry and borrow some more money.
“However, these are not the parables that Jesus chose to tell…” — The Prodigal Son Doesn’t Mean What You Think It Means