The fact that yoga practice accelerates one’s spiritual progress only increases the need for right attitude. Concentration on yoga techniques alone without developing the right attitude can prove dangerous; for spiritual progress can never be forced.
Yoga has its ultimate aim -- the awakening of the kundalini, the tremendous power that lies dormant at the base of the spine. A forceful awakening of kundalini by yoga exercises can prove dangerous, as it destroy the nervous system. The awakening should be by devotional aspiration and not by egoistic power of Yoga. Consider every time you express pure love, or think high thoughts Kundalini sends advance light upward to the brain and every time you think selfish, kundalini moves downward leaving the mind darker.
Attitude is ultimate. One may have right attitude and know nothing of yoga, meditation, and still reach God ultimately. But without right attitude, life time of yoga practice may develop nothing but spiritual pride and develop more outward focus. One has to mix both with saintly people and the worldly people and in all cases the right attitude matters. For even in the worldly sense, those attitudes bear the sweetest fruit which spring most purely from an inner source: self-giving, rather than possessive love; a wish to correct oneself and not others; an impersonal gaze that can enjoy even the world without constant reference to one’s own standing with respect to it.
The realised yogi sees in all things one Divine Self, but novice yogi needs to cultivate in addition to divine impersonal outlook, a more intimate devotional attitude towards God.