The story of the two Indian saints was ultimately derived, through a variety of intermediate versions (Arabic and Georgian), from the life story of the Buddha [REF].
Wilfred Cantwell Smith (1981) traced the story from a 2nd to 4th century Sanskrit Mahayana Buddhist text, to a Manichaean version, which then found its way into Muslim culture as the Arabic Kitab Bilawhar wa-Yudasaf (Book of Bilawhar and Yudasaf), which was current in Baghdad in the 8th century [REF].