Planet Sun in Astrology represents the Soul, the Father, Govt, Power, authority, and how you come out and deal with the people. Simply understand a strong Sun gives you life-giving energy, willpower, immunity, the ability to fight with all evils of your life including infighting with the diseases. A strong Sun basically gives you the power to lead in all odds in life but can also give you aggression leading to self-centered tendencies. On the other hand, a weak Sun can cause a lack of confidence, poor self-expression, and challenging situations vis-à-vis authorities. Sun signifies how will be a person's tolerance level with father and how far you can benefit from your father. Sun with a good association with Jupiter (Guru) shows what all good you will learn from your father as the father is your biggest Guru. Sun with Rahu is like you get all bad habits from your father like smoking, drinking, and other addition. Sun with Ketu shows what good habits and spiritualism you learn from your father and elders. The same way relation of Sun with Venus shows what you give to your wife and what you will get.