A True Guru Guides Us From Experience | Sri Daya Mata 

Good question. Paramahansa Yogananda answered this in the Autobiography of a Yogi: "A question I sometimes hear is this: “Is it true, as certain organizations state, that yoga may not be successfully studied in printed form but should be pursued only with the guidance of a nearby teacher?” In the Atomic Age, yoga should be taught by a method of instruction such as the Self-Realization Fellowship Lessons, or the liberating science will again be restricted to a chosen few. It would indeed be a priceless boon if each student could keep by his side a guru perfected in divine wisdom; but the world is composed of many “sinners” and few saints. How then may the multitudes be helped by yoga, if not through study in their homes of instructions written by true yogis? The only alternative is that the “average man” be ignored and left without yoga knowledge. Such is not God’s plan for the new age. Babaji has promised to guard and guide all sincere Kriya Yogis in their path toward the Goal. Hundreds of thousands, not dozens merely, of Kriya Yogis are needed to bring into manifestation the world of peace and plenty that awaits men when they have made the proper effort to reestablish their status as sons of the Divine Father."