The Treatise on Cosmic Fire, first published in 1925, was the third book jointly authored and holds the inherent testimony that it will remain the main and most enduring part of the thirty-year teaching, despite the depth and usefulness of the volumes published in the series titled Treatise on the Seven Rays or any of the other books.

In the Treatise on Cosmic Fire, the Tibetan provided what H.P. Blavatsky prophesied would be given to us, namely the psychological key to cosmic Creation. H.P. B. stated that in the 20th century, a disciple would come who would provide the psychological key to her monumental work, The Secret Doctrine, the treatise that the Tibetan produced with her, and Alice A. Bailey worked with full recognition of her debt in this succession.

[Excerpt from the text of the introduction of the edition]