It's likely the man has had problems with his son before. That stabbing was most likely the result of a lot of built up tension. But regardless, the father's focus on his son to such a heightened degree is not psychologically healthy. It could also stem from his father generally having too much pride or feeling a lack of respect from everything around him, resulting, again, in a build up of tension within himself rather than specifically with his son. Of course even this is only on the surface, there could be many factors causing this such as alcohol abuse, drugs, work environment, a really bad marriage, scoffing from peers, etc.
and no, this doesn't have much to do with faith. We all have our little lives that these conditions occur in, some have an element of spirituality, some don't, but what we do with our situation is definitely a result of our own specific psychology, which can also be why we are in the situation to begin with, but they are not always directly related. If they WERE completely linked in this case, then you would see many people stabbing their sons in the butts for wearing hats in church.
