The Bhagavad-Gita promulgated the monotheistic or ekantika religion but the Pancharatra system, consisting of the worship of Vasudeva and his several forms, had no organic connection with the work though bhakti or devotion is common to both. This system must have developed in about the third century B.C.

The Pancharatra system is discussed in the Pauskara samhita, the Satvat samhita and the Parama Samhita. The Narada Pancharatra has a section called Jnanamrtasara Samhita. It is entirely devoted to the advancement of the cult of the Krishna of the cow-settlement i.e. Gokula and of his beloved Radha. The vyuhas or forms, which form a peculiarity of the Pancharatra School, are not mentioned in it. This Samhita seems to have been written about the beginning of the sixteenth century. Ramanuja considers this Samhita to be of doubtful authority.

From the Amarakosa it appears that in Amarsimha`s time the four forms or the Bhagavantas recognized the vyuhas of Vasudeva. The proper evidence of the existence of the cult of Vishnu, principally in accordance with the mode professed by the Bhagavatas from the fourth to the eleventh century A.D. is there. The doctrine of incarnation had also become an article of faith with them.

The Gita and some other sections of the Mahabharata represent Vishnu as an ideal divinity and almighty savior working for the salvation of mankind. Vishnu also delights in moral goodness and ritualistic purity and as incarnating from time to time in human or animal form in order to maintain the standard of righteousness. The Narayaniya section of the Mahabharata mentions four incarnations of Vishnu namely boar or Varaha, dwarf or Vamana, man-lion or Narasimha and man or Vasudeva Krisna. Some other verses of the same section mention Rama, Parasurama,Hamsa or Swan, Matsya or fish, Kurma or tortoise and Kalki incarnations of Vishnu. Later Gautama Buddha and Mahavira also came to be recognized as incarnations of Vishnu.