"The Guru", excerpts, Sri Aurobindo

The Guru is the Guide in the yoga. When the Divine is
accepted as the Guide, He is accepted as the Guru.
 The relation of guru and disciple is only one of many relations which one can have with the Divine....
.surrender to the Divine and surrender to the Guru are not the same
thing. In surrendering to the Guru, it is to the Divine in him that one
surrenders-if it were only a human entity, it would be ineffective. But it
is the consciousness of the Divine Presence that makes the Guru a real
Guru, so that even if the disciple surrenders to him thinking of the human
being to whom he surrenders, that Presence will still make it effective.

All true Gurus are the same, the one Guru, because all are the one Divine.
That is a fundamental and universal truth. But there is also a truth of
difference; the Divine dwells in different personalities with different
minds, teachings, influences so that he may lead different disciples with
their special need, character, destiny by different ways to the
realisation. Because all Gurus are the same Divine, it does not follow that
the disciple does well if he leaves the one meant for him to follow
another.

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