Prasna means "question", Uttara means "answer", and Vahini indicates "a stream". This book is the stream of the questions that have evoked answers from Bhagawan Sri Sathya Sai Baba. Among the tasks that Bhagawan has assumed while incarnating, He has declared as basic the one that He calls, "the clarification and purification of the religious scriptures of mankind." Every Vahini emanating from Him has done this service to some aspect or other of the spiritual upliftment of man. This Vahini is one of the earliest in the series, since it seeks to elucidate the fundamental concepts and precepts of religion, especially the technical words and expressions that seek to concretise them. Hitherto published as an Appendix to a single Vahini, the Gita Vahini, it is now placed in the hands of seekers as a key publication, helpful for readers of all the Vahinis. The Ancient Wisdom (Sanathana Dharma), the Perennial Path, has been communicated to posterity in words that have suffered distortion, devaluation, dilution and denigration through the efflux of time and the controversies among commentators. Varna, asrama, yoga, sanyasa, yajna, karmathese are interpreted by dialecticians and practitioners of varied schools and sects, in confusing and contradictory versions. Bhagawan has resolved these tangles. His exemplary love and patience sweeten not only every answer but every question too, for, He has, by posturing as the interrogator, made the clarifications full and fruitful.