Satguru or Sadguru means true guru (Sanskrit सदगुरू sat=true), literally: true teacher. The title means that his students have faith that the guru can be trusted and will lead them to moksha, enlightenment or inner peace. It is based on a long line of Hindu philosophical understandings of the importance of knowledge and that the teacher, guru, is the sacred conduit to self-realization.
"It is very rare to find a Satguru who can give Shaktipat and rare to find a disciple worthy of receiving it. One gets such a Guru only as a result of past meritorious actions."
In the Upanishads, five signs of satguru (true guru) are mentioned.
In the presence of the satguru; Knowledge flourishes (Gyana raksha); Sorrow diminishes (Dukha kshaya); Joy wells up without any reason (Sukha aavirbhava); Abundance dawns (Samriddhi); All talents manifest (Sarva samvardhan).
In one of Kabir's songs the satguru is described as the real Sadhu:
bhâi kôî satguru sant kahâwaî
Hs is the real Sadhu, who can reveal the form of the Formless to the vision of these eyes;
Who teaches the simple way of attaining Him, that is other than rites or ceremonies;
Who does not make you close the doors, and hold the breath, and renounce the world;
Who makes you perceive the Supreme Spirit wherever the mind attaches itself;
Who teaches you to be still in the midst of all your activities.
Ever immersed in bliss, having no fear in his mind, he keeps the spirit of union in the midst of all enjoyments.
The infinite dwelling of the Infinite Being is everywhere: in earth, water, sky, and air;
Firm as the thunderbolt, the seat of the seeker is established above the void.
He who is within is without: I see Him and none else.Songs of Kabir LVI, I. 68 - Translated by Rabindranath Tagore New York, The Macmillan Company (1915)
According to Satguru Sivaya Subramuniyaswami, a Hindu Satguru is always a sannyasin, an unmarried renunciate.Subramuniyaswami, Satguru Sivaya. Living with Siva, glossary. Himalayan Academy Publications. ISBN 0945497989 However, the definition of Satguru elsewhere does not include this strictureGod Speaks, Meher Baba, PUB Dodd Meade, 1955, 2nd Ed. pp. 150,158,196, 291 and there are numerous counter-examples as well, for instance: "Tukaram, a Hindu Sadguru, is known to have had a family. The Qutub Moeinuddin Chisti also had children. The Sadguru Kabir had a son, Kamal, who was very devout." Meher Prabhu, Bhau Kalchuri, Manifestation, Inc. 1986. p.92 - Footnote 1
Other usages
In Sikhism, Satguru is one of the many names for God.
In Sant Mat and Advait Mat the living Satguru is considered the path to God-realizationLewis, James R. Seeking the Light, p.62. Mandeville Press, ISBN 0914829424.
Analogous concepts
The Sufi concept of the Qutub (literally, pole, tower, lighthouse) could be viewed as analogous to the satguru. The Qutub is the shaykh who provides a focus for spiritual teachingsAhmed, Nazeer. Islam in Global History: From the Death of Prophet Muhammed to the First World War, Xlibris Corporation, ISBN 0738859664. Other terms include Pir and Sarkar.
Jacques Vigne, in his book Indian Wisdom, Modern Psychology and Christianity asserts that John the Baptist might be looked upon as someone very much like a satguru. Vigne, Jacques (1997). Indian Wisdom, Modern Psychology and Christianity, Part II, Ch. 1. B. R. Publishing Corporation. ISBN 8170189446. Available online