If I wrote that homily... Thoughts on the Prodigal Son
At first glance, this beautiful parable offers the obvious opportunity for catachesis on the Church's understanding of the Sacrament of Reconciliation, which is grounded in such basic Scriptural passages as Matthew 18 and James 5. Such catachesis could be attended by explanations of baptism as the total re-formation of the person, such that the penitent can become an active agent in his own restoration through the acts of penance; these explanations could be followed by an explanation of the doctrine of Purgatory and the practice of indulgences.
On another level, however, the same parable employs such rich emotional language as would lend itself well to a consideration of the divine impassibility, wherein God's unfailing love manifests itself both in unchanging anger towards sin and disobedience, and in simultaneous and absolute readiness to run to the returning penitent in extravagant mercy. The ostensibly mysterious doctrine of God's impassibility is facilitated by such passages as Augustine's beautiful encomium near the beginning of the Confessions:
Oh my God... who art most beautiful and most strong; stable, yet not supported; unchangeable, yet changing all things; never new, never old; making all things new, yet bringing old age upon the proud, and they know it not; always working, ever at rest; gathering, yet needing nothing; sustaining, pervading, and protecting; creating, nourishing, and developing; seeking, and yet possessing all things. Thou dost love, but without passion; art jealous, yet free from care; dost repent without remorse; art angry, yet remainest serene. Thou changest thy ways, leaving thy plans unchanged; thou recoverest what thou hast never really lost. Thou art never in need but still thou dost rejoice at thy gains.
Finally, it is significant that the parable of the Prodigal Son has recently been treated by scholars such as N.T. Wright, who have explored the story's potential to clarify the relationship between Israel and Gentile Christians allegorically: with the elder brother who has "always been with the Father and who shares all that the Father has" treated as Israel, and with the younger brother who has squandered being treated as the Gentiles who have rebelled against the most basic mandates of their natural and moral responsibilities, we see the Biblical understanding of the Christian and Jewish ecclesiae as brothers reunited in the one human family inaugurated by the Incarnation of the Creator.