This set of books is a collection of the transcripts of 132 Raja Yoga lectures given by Swami Sarvagatananda between September 1977 and June 1981 on the Yoga Aphorisms of Patanjali. The book includes the question and answer session that followed each class.The classes were given at the Ramakrishna Vedanta Society of Massachusetts in Boston. His many examples for spiritual living reflect life in America.

One of the students writes in the preface:

About thirty of us, college students, professors, office workers and retirees had the good fortune to participate in these classes. It was a character transforming experience for us. We learned that Raja Yoga deals primarily with the mind and its control. But this control cannot be attained without leading a pure life, full of loving concern for all, and reflecting rather than reacting to negative thoughts or circumstances.

As the classes progressed, the intensity increased. We listened in fascination as the swami went deeper into the intricacies of the mind, the method of concentration and its culmination in meditation. The swami's intimate knowledge of this difficult subject enabled him to clear up all our doubts in simple yet convincing language in a question and answer session at the end of class.