A good rule of thumb is that every guru is false until proven authentic. In these days, when spiritual teachers are as plentiful as taxicabs in springtime New York, you must first make sure that the one you choose knows where he's going, and how to get you there without causing you needless and costly delay.
Unfortunately, the matter is not as simple as checking for a proper "guru's license." A true guide's credentials are considerably more subtle than a certificate on the wall or, more appropriately, an ocher robe and sting of sacred beads.
Mere intellectual glibness on spiritual subjects, or familiarity with great religious scriptures, is often naively mistaken for a sign of spiritual advancement. Yet intellectual prowess in itself can never be a substitute for inner attainment, for it can and often does coexist with petty egoism, selfishness, and a complete disregard for others. A real spiritual master can be recognized only by the fine-spun qualities which pervade his day-to-day living.
The crucial point: Satisfy yourself, before you decide to follow a guru, that he is authentic. Just as you would not give a raw diamond to be cut by a blind man, you do not want to entrust your spiritual odyssey to one who sports the façade of attainment but does not taste the experience of gnosis. As one master, mincing no words, has aptly put it: "To put yourself in the care of an imperfect master is like letting a madman sit on your chest with a knife in his hands!"
How To Choose A Guru, written by Rick Chapman and first published by Harper and Row in 1973, addresses dozens of topics concerning spirituality and mysticism from the perspective of Meher Baba's teachings.