The ninth chapter of the Bhagavad Gita is called the Rājavidyā-rājaguhya-yoga, which can be translated as the “Yoga of Royal Knowledge and Royal Secret.” This chapter continues the discussion of the nature of God and his relationship with the world, and emphasizes the importance of devotion to God as a means of attaining spiritual liberation.
One of the main themes of this chapter is the idea that God is the source of all beings and the ultimate goal of all spiritual practice. Krishna explains that those who worship other gods or perform other spiritual practices with the goal of attaining worldly rewards are ultimately misguided, and that true spiritual knowledge and liberation can only come from devotion to God.
Krishna also reveals a “royal secret” to Arjuna in this chapter: the knowledge of the supreme Self, which is the ultimate goal of all spiritual practice. He explains that the Self is present in all beings and is the source of all consciousness and knowledge. By realizing the Self, one can attain liberation from the cycle of birth and death.
The Rājavidyā-rājaguhya-yoga is also notable for its emphasis on the importance of bhakti, or devotion to God, as a means of attaining spiritual liberation. Krishna explains that those who have devotion to him are the most dear to him, and that he will guide them towards the ultimate goal of liberation.
Overall, the Rājavidyā-rājaguhya-yoga is a profound and inspiring chapter of the Bhagavad Gita that emphasizes the importance of devotion to God and the ultimate goal of spiritual liberation.