Like the Prodigal Son and his brother, people can be strangers, even though they live in the same house. We can feel lonely in the middle of a crowd. We can be lonely in the presence of just one person. We are not able to break through to the center of that other person. And that other person cannot pass beyond the barricades we have built around ourselves.
Sin is that which divides life from life and prevents community.
Instead of referring to our gospel story as the Prodigal Son, we might better name it the story of the Forgiving Father. A father had two sons, and both of them rebelled against him. One took up residence in a distant land, accepting the gifts of his father but rejecting the father's presence. The other remained at home but refused to share his father's sorrows and joys. In a way this is a description of so many of us.