The themes developed in the excerpt are the following ones:
a- kinship
and
c- tradition vs change
Kinship: blood relationship. The excerpt shows a father talking about and disapproving of his son. The father can't believe his own son behaves in such an erratic way (according to how he feels about it). We can see it in the following passage: "For how else could he explain his great misfortune and exile and now his son’s despicable behavior?"
Tradition vs change: the father criticizes his son for having abandoned family traditions and for hanging out with a bunch of atypical guys: "To abandon the gods of one’s father and go about with a lot of effeminate men clucking like old hens was the very depth of abomination."