There are four different paths to follow: abstinence (hatha yoga), devotion (bhakti yoga), learning from the experiences of life (raja yoga), and the fourth one, dhyana yoga or mantra yoga, which means attaining spirituality by wisdom. But in every one of these paths a teacher is needed. It is his blessing, his guidance that helps; it is the contact with him that is important. A real teacher is only an instrument of God. It is his presence, his wish for you that helps, not the words which he is saying.