Synopsis When I attended a seminar and Vipassana course during December, 20, 1986 to January, 1, 1987, at Vipassana Research Institute, Dhammagiri, Igat Puri (Nasik) under the guidance of Kalyana-mitta S.N. Goenka Ji, the master used to refer to the verses of Guru Nanak, occasionally, during his discourses. Once, I put this question to him as to why does he quote Guru Nanak while talking on Vipassana? His instant reply was that Guru Nanak also practised Vipassana. In this very meeting, Goenka Ji very emphatically suggested that I should explore the sources of Vipassana in Gurubani. I propose to work on, as inspired by Goenka Ji, The Path of Purification based on the Sikh scriptures. But, before that, I wanted to explore the sources of Vipassana in Pali literature. This collection of papers provides theoretical framework of Vipassana although, Vipassana is a subject of practice, but nonetheless, theory is one aspect of practice.