Devotee: Some of these so-called gurus will say some things that Krishna says, but they'll give other instructions also. What is the position of such persons?
Srila Prabhupada: They are most dangerous. Most dangerous. They are opportunists. According to the customer, they give some teachings so he will be pleased. Such a person is not a guru; he's a servant. He wants to serve his so-called disciples so that they may be satisfied and pay him something. A real guru is not a servant of his disciples; he is their master. If one becomes a servant, if he wants to please the disciples by flattering them to get their money, then he is not a guru. A guru should also be a servant, yes--but a servant of the Supreme. The literal meaning of the word guru is "heavy"--heavy with knowledge and authority, because his knowledge and authority come from Krishna. You cannot utilize the guru for satisfying your whims.
- Journey of Self Discovery 2.2 Beyond Religion