Adi Shankaracharya was an enlightened spiritual Master, thought to have lived in the eighth century, who articulated and spread throughout India the teachings of Advaita Vedanta, a philosophy that focuses on the oneness of the individual soul and God.
Gurumayi Chidvilasananda and Baba Muktananda have on numerous occasions brought seekers' attention to Shankaracharya's teachings, which elucidate concepts central to the philosophy of the Siddha Yoga path. Shankaracharya's written works, which include the Vivekachudamani and Atmabodha, expound the eternal nature of the supreme Self and the significance of the Guru in a seeker's sadhana. He also writes of the importance of performing spiritual practices such as meditation, mantra japa, and contemplation as a means to achieve liberation.
Shankaracharya is credited with the founding of four monastaries in India—one in each of the cardinal directions—and with the establishment of ten different orders of sannyasins, monks. One of these is the Sarasvati Order to which Baba, Gurumayi, and all the Siddha Yoga Swamis have been initiated.