6.28 Thus, in the above - said manner, devoting himself to the Yoga of the self and by that means expelling all old impurities, the Yogin attains 'perfect', i.e., boundless felicity at all times easily, without stress and strain. The felicity is born of the contact with the Brahman (Atman), meaning the joy of experience of the Brahman. Now Sri Krsna says that the mature stage of Yoga consists of four degrees, as stated in the succeeding verses from 29th to 32nd.