Shri Sai Baba of Shirdi was a Yogi and a Guru who gave the world the keys of happniess - Shraddha (Faith) and Saburi (Patience). He never asked his followers to abandon their religion. His life exemplified Love & Forgiveness, Charity & Contentment, and Devotion to Guru & God. His teachings combined elements of Hinduism & Islam and tried to achieve communal harmony between the two religions.
He drew devotees from all over the country though he never traveled and never cared for fame. Over and over his devotees found he knew their innermost thoughts and details of their lives. He effected cures, conferred health, happiness, and prosperity, and made childless couples conceive. His real purpose though was to awaken in them a longing for the spiritual life. Thousands thought of him as a wonderful saint with miraculous powers but his innermost circle knew him to be in incarnation of God himself. Some said of Datta, others of Shiva, still others saw ecstatic visions of their own beloved Guru or chosen Ishta (personalized icon of God) while gazing at Him. He himself said only that he was the humble servant of God and pleased and furthered all who came in contact with him. Many books have been written about Shirdi Sai Baba but the Shri Sai Satcharita, the story of Sai Baba's life and actions (quoted from below) was written in his own lifetime and is best known among Sai devotees. Just before leaving his body he told a disciple he would be reborn in a certain village 8 years hence and so it came to pass. (See section on Sathya Sai Baba.)
Sai Baba was first seen as a youth of sixteen sitting under a neem tree in Shirdi. None knew his origin or past. Even then he seemed to be full of the knowledge of Brahman. He had no desire for worldly objects even in dream. He kicked out Maya (illusion) and Mukti (illumination) was serving at his feet. This young lad, fair, smart, and very handsome, was first seen under a Neem tree seated in an Asan (meditative posture). The people of the village were wonderstruck to see such a young lad practicing hard penance, not minding heat and cold. By day he associated with none and at night he was afraid of nobody. People were wondering whence that young chap turned up. His form and features were so handsome that a mere look endeared him to all. He went to nobody's door, always sat near the Neem tree. Outwardly he looked very young; but by his action He was really a great soul. He was the embodiment of dispassion and an enigma to all.
A saint name Gangagir who frequented Shirdi said of him on first setting eyes on him "Blessed is Shirdi, that it got this precious jewel". Another saint by name Anandanath said "This is a precious diamond in reality, though he looks like an ordinary man. You will realize this in the near future."
Peace or calm was his ornament and he was the repository of wisdom. He had no love for perishable things and was always engrossed in self-realization. He did not know or care for honor or dishonor. The name of Allah was always on his lips. His inside was as calm as the deep sea. Though he sat in one place, he knew all the transactions of the world. Though a Siddha (realized being), he acted like a sadhaka (disciple on the spiritual path). He was meek, humble, and pleased all..
Shortly after coming to Shirdi, Baba displayed his mastery over matter. He was fond of lights and used to borrow oil from the shop keepers to keep earthen dishes with wicks burning the whole night in the masjid (temple). After a while the shop keepers got together and decided not to give oil. Then they watched to see what Baba would do. Unperturbed, Baba poured water into his oil pot, took a drink from it, then filled all his earthen dishes with it and lighted them. To the surprise and dismay of the shopkeepers, the wicks began to burn and kept burning the whole night. Afterwards the shopkeepers repented and apologized.