About the book: 2009 / This volume is the last book in the six-volume edition of “Letters on Yoga” in Russian. This book discusses the transformation of a person’s physical being, which should become the culmination of his internal, spiritual transformation and lead to the appearance on Earth of a new, “superhuman” being, possessing not only a divine, “supramental” consciousness, but also an immortal body. Such a radical and comprehensive transformation is associated with numerous difficulties and dangers caused by the confrontation of hostile forces of the subtle-material planes of existence. Therefore, this book is extremely important for those who intend to practice Integral Yoga, as it contains detailed explanations and recommendations designed to make spiritual practice safe.