Ramanujacharya attempted to synthesize Vaishnavism with Vedanta. He was vehemently opposed to Shankara’s Adwait and assailed it tooth and nail. Ramanuja’s philosophy is theistic.
According to him, God is free from all faults and defects. He is creator, preserver and the destroyer of the world. He appears in five different modes:
1. Para or the highest, in which mode Narayan, also called Parabrahman and Para-Vasudev lives in a city called Vaikuntha. He is attended to by Sri Bhy and Leela (Goddess Lakshmi, Earth and Sport).
2. Vyuha in which the Para has assumed four forms, viz. Vasudev, Sankarshana, Pradyumna and Anirudha for conventional worship.
3. Vibhava which mode consists of the ten avatars or incarnations.
4. Antaryami in which mode he dwells in the heart and can be seen only by yogis and accompanies the individual souls even when they go to heaven or hell.
5. Idols or images set up in the houses, villages or towns made up of materials chosen by the worshippers.
It is thus clear that Ramanuj derived his metaphysical doctrines from texts of upnishads and the Vedant Sutras, while his theory about the creation of the world has been adopted from the Puranas and is based on the 25 elements of Sankhya philosophy.
His Vaishnavism is the- old Vasudevism of the Panch-Ratra system. In Ramanuja’s philosophy devotion or bhakti is continuous meditation of the Supreme soul.
It thus corresponds to the upanishadic texts and Vedant Sutras of Badrayan. It takes cue from the Bliagvat Geeta as well.