Satchidananda alone is the Guru - Sri Ramakrishna

Brahmo: "Is spiritual knowledge impossible without a guru?"

Master(Sri Ramakrishna): "Satchidananda alone is the Guru. If a man in the form of a guru awakens spiritual consciousness in you, then know for certain that it is God the Absolute who has assumed that human form for your sake. The guru is like a companion who leads you by the hand. After the realization of God, one loses the distinction between the guru and the disciple. 'That creates a very difficult situation; there the guru and the disciple do not see each other.' It was for this reason that Janaka said to Sukadeva, 'Give me first my teacher's fee if you want me to initiate you into the knowledge of Brahman.' For the distinction between the teacher and the disciple ceases to exist after the disciple attains to Brahman. The relationship between them remains as long as the disciple does not see God."

-The Gospel of Sri Ramakrishna