These characteristics are described in the Digha Nikaya's "" (D, I:142). Some Hindus regard Gautama as the 9th avatar of Vishnu. However, Buddha's teachings deny the authority of the Vedas and the concepts of Brahman-Atman. Consequently Buddhism is generally classified as a "nāstika" school (heterodox, literally "It is not so") in contrast to the six orthodox schools of Hinduism. In Sikhism, Buddha is mentioned as the 23rd avatar of Vishnu in the Chaubis Avtar, a composition in Dasam Granth traditionally and historically attributed to Guru Gobind Singh. Classical Sunni scholar Tabari reports that Buddhist idols were brought from Afghanistan to Baghdad in the ninth century. Such idols had been sold in Buddhist temples next to a mosque in Bukhara, but he does not further discuss the role of Buddha. According to the works on Buddhism by Al-Biruni (973–after 1050), views regarding the exact identity of Buddha was diverse. Accordingly, some regarded him as the divine incarnate, others as an apostle of the angels or as an Ifrit and others as an apostle of God sent to human race. By the 12th century, al-Shahrastani even compared Buddha to Khidr, described as an ideal human. Ibn Nadim, who was also familiar with Manichean teachings, even identifies Buddha as a prophet, who taught a religion to "banish Satan", although not mention it explicitly. However, most Classical scholars described Buddha in theistic terms, that is apart from Islamic teachings. Nevertheless the Buddha is regarded as a prophet by the minority Ahmadiyya sect, generally considered deviant and rejected as apostate by mainstream Islam. Some early Chinese Taoist-Buddhists thought the Buddha to be a reincarnation of Laozi. Disciples of the Cao Đài religion worship the Buddha as a major religious teacher. His image can be found in both their Holy See and on the home altar. He is revealed during communication with Divine Beings as son of their Supreme Being (God the Father) together with other major religious teachers and founders like Jesus, Laozi, and Confucius. The Christian Saint Josaphat is based on the Buddha. The name comes from the Sanskrit "Bodhisattva" via Arabic "Būdhasaf" and Georgian "Iodasaph". The only story in which St. Josaphat appears, "Barlaam and Josaphat", is based on the life of the Buddha.