The deification of man is another feature of post-Vedic religion. Great heroes, considered as gods, came down to the earth as men for the protection of humanity, and were worshipped as gods in temples erected for them. A typical instance of this process which continued till recent times is the goddess Karniji in Rajputana. In the Vedas also human beings became gods like the Maruts and the Rbhus and human beings attained to divine powers and some of the divine rights, e.g. the rsis known as Angiras. But there is no mention in the Vedas of gods coming down to earth as human beings. In post-Vedic Hinduism God appeared also in the form of animals. There is Hanumana, the monkey god. There is Ganesha, the man-elephant god. Nandin, the attendant on Siva, has the form of a bull. Skanda or Subrahmanya has the form of a serpent. The avatara doctrine associated with Vishnu is, however, a later development.
There is only one avatara of Vishnu for which there is a trace in the Vedas. That is the Dwarf, who measured out the whole world in three steps. From the word varaha which occurs in the Veda, commentators have tried to show that this is a reference to the Boar incarnation (varaha), but there is no basis for this interpretation. All the other avataras of Vishnu are extra-Vedic.
The gods in the Vedas have little individuality and hardly any concreteness. But the entire conception of God changed in later Hindu thought. There is greater clearness owing to the more concrete nature of the divine form and the greater differentiation in the functions of the gods. Brahma was assigned the function of creation, but as this remained an abstract conception he dwindled in religion though he continued to find a place in mythology. Siva and Vishnu, on the other hand, became concrete and highly individualized and took the highest position in Hindu thought. The image of Vishnu reposing on the coiled body of the serpent Shesha, with his two consorts Sri and Bhumi, and with his functions of preserving and protecting the world cannot be derived from the conceptions of God we find in the Vedas. The same applies to Siva on the Mount Kailasa, with his consort Parvati, and his sons and attendants, and charged with the destruction of the world so that there may be a better creation. Ganesha, Skanda and other deities acquire distinct individualities and distinct functions.
The growth in personification helped in the development of the doctrine of bhakti in Hinduism. We find traces of bhakti also in the Vedas, especially in the hymns to Varuna; but how can true bhakti evolve with the Vedic gods who are incorporeal and abstract and cannot be seen even in the form of idols? Vedic sacrifices remained domestic or village institutions and it was temple worship that assumed the form of national institutions.