Though Narendra could not accept Ramakrishna and his visions, he could not neglect him. It had always been in Narendra's nature to test something thoroughly before he could accept it. He tested Ramakrishna to the maximum, but the master was patient, forgiving, humorous, and full of love. He never asked Narendra to abandon reason, and he faced all of Narendra's arguments and examinations with infinite patience. In time, Narendra accepted Ramakrishna, and when he accepted, his acceptance was whole-hearted. While Ramakrishna predominantly taught duality and Bhakti to his other disciples, he taught Narendra the Advaita Vedanta, the philosophy of non-dualism. During the course of five years of his training under Ramakrishna, Narendra was transformed from a restless, puzzled, impatient youth to a mature man who was ready to renounce everything for the sake of God-realization. Soon, Ramakrishna's end came in the form of throat cancer in August 1886. After this Narendra and a core group of Ramakrishna's disciples took vows to become monks and renounce everything, and started living in a supposedly haunted house in Baranagore. They took alms to satisfy their hunger and their other needs were taken care of by Ramakrishna's richer householder disciples. source: http://en.wikipedia.org/wiki/Swami_Vivekananda