In astrology Sun and Saturn are considered enemies of each other. The gods or the demi-gods cannot behave like mortals. So we have to analyse the concept of enemies in a context and appropriate meanings. The Sun is truth, Sun is Knowledge; Sun is light. It is the place where our ancestors would ultimately go. After vasu and rudra , where our fathers are believed to have attained the status and receive pinda from us, the ultimate loka or state comes Aditya . Vasu rupe~, Rudra rupe~ and finally Aditya Rupe~.. The Sun is the embodiment of all gods. He is the ultimate. He is the destroyer of sins.
The concept of sin is co-terminus with the life we live in this world. The past actions which are sinful, in our past lives give the results of miseries in this present world. The miseries depend upon the degree of sins we committed in our past lives. There two gods who are attributed with the quality of destroying one's sins. Firstly- Lord Shiva. Secondly the demi god Sun. It is easier to pray Lord Shiva and wash out our past sins. But the Second way is tougher one. Adithya is not easier to please. He is a strict disciplinarian. In the first and easier way of pleasing Lord Shiva, there are chances of we committing sins again. But the Second and tougher way is final.
It is born out of ultimate truth, knowledge and karma. It is this tough path that is chosen by the Rishis in doing tapasya. ( For detailed study - see concept of sin). Step by step one attains the state of Aditya and his material life comes to an end, which is the goal of all truth seekers. It is the freedom from bondage of birth and re-births. It is the attainment of god-hood.
The Sun burns everything. Our ignorance, our beliefs, our knowledge, which are born out of lies, images, maya , which is thrown by Rahu on our monds. The knowledge and beliefs are so strong and deep rooted in our minds, in our actions, we refuse to believe the ultimate truth. We are programmed to take shelter under clouds, false roofs, such as a frog taking a shelter under a serpent. This state of mind and our actions are created and developed by Saturn. Saturn is the representative of our false shelter. He creats maya through Rahu. All the dirt, whether in mind or in our physical presence in this world, is the abode of Saturn. He will not direct us to the path of truth, knowledge and god. He creates falls, pits and blindness, so that we eternally revolve round and round this maya. This maya is so powerful and strong, even the mighty Sun cannot escape.
So the two planes of operation of the fields are quite different. The concepts of Sun and Saturn go directly opposite to each other. Both act according to our past actions or karma. They are not enemies of each other. Because no two gods have the feelings of hatredness or love. They are above all those trivial behavior. They are above such meanness. They act according to their natures. Both are necessary embodiments of this worldly life. Sun is the enemy of ignorance, false-hood, indiscipline, and maya. The Saturn is the enemy of light, discipline, truth and knowledge. The Saturn is the creator maya.
All these qualities are the embodiments of mortal lives in this world; and definitely not the qualities of either the Sun or Saturn. In this way both are supplementary and complementary to each other. They are not enemies; But the gods acting in tandem, in harmony. One takes up where the other ends. They are the enemies of certain actions of mortals. It is the mortal to choose his action. If one sincerely attempts , penaces and disciplined it is the Saturn who is more pleased and he withdraws the curtain of Maya from one's path of seeking truth. Then the Sun condones and destroys the earlier sins and shows the path of liberation through his light.