Hinduism also tell us about Gurus. There were no such people who became great without following there gurus. And this is not the matter of religion. Every religion teach us about having a Satguru. For eg Vivekanand was able to spread his thoughts by the grace of his guru Swami Rama Krishna Paramhansa. Every time we read about him we know that Vivekananda was in search of God. Then why he couldn't get it by himself. He was able to see God by the only grace of his Guru. Once again I want to tell Guru is not merely a human being. He is between human and Parmatma. The same was said by Lord Krishna in Bhagwat Gita. Bulleshah was not Hindu but he made his guru his life. He prayed him by the depth of his heart. A Guru is not a person who just give us knowledge verbaly but but proves it practically.