What is the ruling on shunning a father who sexually assaulted his son's wife and caused their divorce, knowing that they live in the same house, and one's soul recoils from speaking to him?

Your father has committed a grave error, and you must advise him and call him to repentance. This act does not nullify his right to your dutifulness; therefore, you must be dutiful to him and obey him in what is good, and do not abandon him. Rather, associate with him with kindness and treat him well, along with offering him advice. Your dislike for him in your heart will not harm you. Be cautious of him in the future by marrying in another home and preventing your wife from being alone with him, unless clear signs of sincere repentance appear from him.