Srimad Bhagavad Gita -Ramanujacharya
Chapter-15 Puruṣottama Yogaḥ
The Mystery of the Omnipresent Supreme Being
Summary of the Teaching
the 13th chapter the nature of Prakrti and Purusha was analysed; it was taught that from time out of mind the immaculate Jīva comprised entirely of infinite consciousness, conjoins with Material Nature (Prakrti), and is embodied in the forms of gods etc., This produces the cycle of attachment to the Modes of Material Nature (Gunas). Then followed in the 14th chapter the teaching concerning the Gunas was elaborated upon and then it was taught that Devotion to Krishna leads to detachment from the Gunas which in turn results in the realisation of the true nature of the Self.
Now in this 15th chapter, Sri Krishna, the adorable Lord reveals Himself as being in absolute control of the universe; both perishable (Kṣara) or bound Jīvas and the imperishable (Akṣara) or liberated Jīvas. He also states that He is the Supreme Being because of His supernal greatness in being antithetic to all that is negative and being the font of auspicious attributes. He is different in kind from both the perishable and imperishable Jīvas which constitute His Modes.