This passage appears in the RCL for Year C during Lent. (Lastly: March 6, 2016)
Summary: Like other great and familiar stories, the prodigal son does not require anything overly advanced. The best thing we can do is help our listeners slow down, ponder the story and dwell on its many meanings, most of which are not too secretive. But if you want something to chew on...recently I have been reflecting on how modern humans are Homo Economicus, defined by our market based relationships. This passage presents some very interesting connections between money, life and happiness. Both sons must learn that true relationships are based on compassion and grace, not the exchange of goods and services. Yet true relationships reveal themselves in exchange of goods and services.
σου (of you, vs 30). This is a little word, but it is significant (and its meaning clear in English). The older brother considers his brother only a son of the father (your son!). The father explains that it is actually his brother (your brother). Economic relationships can be severed, but blood relationships cannot (or not without some serious difficulty).
ουσιας and βιον ("estate" and "money" in vs 12). These words mean more deeply "life" or "essence." (Think: Ousia from "one ousia three hypostasis"; and bios in "biology"). It is striking that the Father is asked and gives not simply of his money, but of his essence, his life, his estate. There is a strong relationship between what the Father has and who the Father is. Both sons perceive correctly that the Father's giving away of possessions reveals something about his character. What we have to give is reflective of who we are. To think about it different, to know Christ is to know Christ's benefits (as Luther said).
καλλαω ("be employed" in vs 15). This word actually means cling. (Husband shall cling to his wife). How many of us are clung to our jobs? The assumption is that the economic relationship will provide a basis for existence. But it does not. The younger son is only the hired hand (μισθιων). In fact, when he seeks to return to his father, he offers to become a hired hand, where the relationship would be simply economic between him and his father.
εσπλαγχνισθη ("compassion," vs 20). This word means, literally, intestines. The idea of Greek compassion is that when you have compassion on someone, your insides get tight. The father has compassion on the son.
παρακαλει ("encourage," 28) I think it interesting that the verb here for encourage is related to the word for Holy Spirit (paraclete). We confess in the Apostle's Creed a belief in the forgiveness of sins and put that with the Holy Spirit. We definitely need the Holy Spirit to enable us to forgive each other.