Gautama Buddha is mentioned as an Avatar of Vishnu in the Puranic texts of Hinduism. In the Bhagavata Purana he is twenty fourth of twenty five avatars, prefiguring a forthcoming final incarnation. A number of Hindu traditions portray Buddha as the most recent of ten principal avatars, known as the Dashavatara. Siddhartha Gautama's teachings deny the authority of the Vedas and consequently Buddhism is generally viewed as a nāstika school from the perspective of orthodox Hinduism. Many of the eighteen orthodox Puranas mention the Buddha in a less favouring light. They present the birth of the Buddha as a ploy by the Supreme God Vishnu to corrupt demons and sway them from Vedic teachings. Only by leading them astray with his teachings could the demons be destroyed. This belief is sometimes associated with the Asuras of Tripura as well as others. Literature from the International Society for Krishna Consciousness, on the other hand, maintains that Krishna took the appearance of an atheistic teacher out of benevolence, in order to trick atheists into worshipping God.
Some early Chinese Taoist-Buddhists thought the Buddha to be a reincarnation of Lao Tzu. In Japan, since one of the symbols of Dainichi Nyorai was the sun, many equated Amaterasu, the Sun Goddess, with a previous reincarnation of Dainichi Nyorai.
Ahmadiyyat
, the Fourth Caliph of the Ahmadiyya Community, in his book Revelation, Rationality, Knowledge & Truth, argues that Buddha was indeed a prophet of God who preached Monotheism. He quotes from the inscriptions on Ashoka's stupas which mention "Isa'na" which means God. He quotes, "'Thus spake Devanampiya Piyadasi: "Wherefore from this very hour, I have caused religious discourses to be preached, I have appointed religious observances that mankind, having listened thereto, shall be brought to follow in the right path, and give glory to God*." The Ahmadiyya hold the view that the Buddha was indeed a Prophet of God. Mirza Tahir Ahmad has also stated that the Qur'anic figure called Dhul-Kifl may have been the Buddha in his book "An Elementary Study of Islam." In fact, a verse in the Qur'an quotes that God has sent many prophets to thee. However, only a few have been named. It is believed by some that Buddha may have been a Prophet of God sent to his people who taught Monotheism.
Christianity
The Greek legend of "Barlaam and Ioasaph", sometimes mistakenly attributed to the 7th century John of Damascus but actually written by the Georgian monk Euthymius in the 11th century, was ultimately derived, through a variety of intermediate versions from the life story of the Buddha. The king-turned-monk Ioasaph ultimately derives his name from the Sanskrit Bodhisattva, the name used in Buddhist accounts for Gautama before he became a Buddha. Barlaam and Ioasaph were placed in the Greek Orthodox calendar of saints on 26 August, and in the West they were entered as "Barlaam and Josaphat" in the Roman Martyrology on the date of 27 November.