The notion of personal God with whom most intimate relations could be established by the devotee is the focus of theistic religions consciousness. The deities Vishnu and Shiva come to the fore front while Brahma the creator is thrust into the background. In the middle ages the doctrines of the Vaishnavities acquired a philosophy.
Buddhism may have influenced the new form of piety - the Bodhisattava looking down in love and pity and helping the creation was probably earlier than any comparable idea in Hinduism. The sect of the Bhagavatas worshippers of Vasudeva was active at least a century before Christ.
The emergence of clear cut theism of Hinduism is to be found in the two epics the Ramayana and the Mahabharata. Both Rama and Krishna are treated as the incarnations of Vishnu the benignant and merciful God. He is not the God of mercy but also the God of Beauty. Rama is the Dharmaraja. The idea of God the Beautiful the Captivator of hearts finds its acme in the Bhagavata purana.
In the religious philosophy of the Mahabharata we observe the gradual relaxation of the idea of the non-duality. Dualism is inevitable for the generation of bhakti by the loving devotion to God. Yoga which originally meant physicopsychological discipline leading to the stillness of mental activities now becomes a method of sitting one self enrapport with the divine who is the Inner Ruler Immortal both in the soul of man and in the universe outside of him. Thus Yoga becomes a way of life a method of communion with God but is not however a great repression of desires or the forcible expulsion of disturbing thoughts.
The new aspects of this theistic religion are love and grace reconciliation of the immense and transcendence of God and finally the view that the path of deliverance lies through heart's devotion rather than through laborious travail of cerebration. Bhakti there fore is an easier path of deliverance than jnana saivism too developed a theology adapted to devotion and literature. Tamil saivism teaches the reality of the three categories God souls and matter. In salvation the soul is united but not identified with the deity. Tamil saivism thus does further in the direction of dualism than the qualified monism and Ramanuja.
The theist concept of Vishnu and Shiva have the common content of Bhakti element. Both are more dvaitic than advaitic. The Bhagwad Gita shows wonderful confluence of currents of philosophic and religious thoughts. The Gita clearly shows that there is compelling need for a personal God.