This teaching is a teaching the Vidyadhara Chögyam Trungpa Rinpoche gave his disciple Rigdzin Shikpo while still staying in Scotland. You can find the full version of this pithy teachings plus some info on the background in "the collected works of ctr" book number 1, selected writings.
"Trungpa Rinpoche gave the Maha-Ati teachings in this text directly to me from his personal inspiration; they weren't translated from Tibetan, but emerged from his insight, based, I'm sure, on traditional Dzogchen upadesa [instruction or teaching]. I wrote them down over a period of time with Rinpoche's guidance and encouragement, linking them together using his terminology. The text was probably completed in 1968 at Biddulph Old Hall, shortly before Rinpoche left for India . Some time later the text was translated into Tibetan so that Dilgo Khyentse Rinpoche could check what was said; as far as I know he approved. Thus there seems to have been a textual translation involved, but remarkably it was from English into Tibetan!
After Rinpoche left Britain , some copies of the text found their way into hands other than those of his students. It was published in part by Dr. John Crook in his The Yogins of Ladakh and more com pletely in Chime Yungdung's magazine Vajra. This latter version was photocopied and circulated within Vajradhatu [the main organization founded by Trungpa Rinpoche in the United States ]. Unfortunately the text was incorrectly described in Vajra as a translation made by Rinpoche and me; there was also confusion in places between the main text and the interleaved commentary and the title was changed to "Maha-Ati."
Alone this might not have mattered too much, but in the Sham bhala Sun of September 1998 and subsequently in the Shambhala Sun website up to the present day, a new version of the text appeared, full of arbitrary, idiosyncratic editorial changes. The Vajra version with its errors was used as the basis for this . . . revision.
Rinpoche referred to the original text as self-secret, so it's proba bly suitable for a wider distribution than most Vajrayana texts, but I feel it's important to keep to Rinpoche's intention as closely as wecan.... It may help matters if the original text is published, so I have attached it to this e-mail.''
For The Collected Works Rigdzin Shikpo has provided the authoritative and original edition of this text. Its editor continues to live in Oxford , where he and Rinpoche originally met. He was one of Trungpa Rin poche's early students in England and continued to study with him until Rinpoche's death. He was one of the first truly scholarly students that Rinpoche worked with, and he took voluminous notes on their conver sations about many aspects of Buddhist doctrine and practice, particu larly focused on the ati teachings. With encouragement from his teachers, he later founded the Longchen Foundation as a vehicle to fur ther the study and practice of this tradition, and he continues to teach in England . Another article that he and Chögyam Trungpa worked on together, on teachings related to the Tibetan Book of the Dead, appears in Volume Six of The Collected Works."- foreword of the collected works book one