The resources provided here may prove helpful to those exploring the mysteries of O.T.O., Thelema, and magick. These resources include some of my own works, and also those of others that I recommend.

Note that in most sources from before mid-2016 my name is given as "Craig Berry". In some sources I am referred to by my episcopal name, "T Ce Acatl".


  • "The Triple Inequality" - Thoughts on the relationship between Crowley, Thelema, and the O.T.O.

  • "A Structural Model of the Collects" (Agape 14.1-2 p. 10) - An attempt to explain the nature and ordering of the Collects in the Gnostic Mass.

  • "One Reed: Quetzalcoatl and the Unity of Sacrifice" Unity Uttermost Showed: Proceedings of the Seventh Biennial National Ordo Templi Orientis Conference (on Amazon) - An examination of the relationship between Aztec myth and the formula of sacrifice in the Gnostic Mass.

  • "Quintessential, Once Again: A report from the path of gender transition" For the Chance of Union: Proceedings of the Eleventh Biennial National Ordo Templi Orientis Conference (on Amazon) - A discussion of my own path into gender transition, and of gender magick in general.

  • "Holy Season Meditations" - Many Thelemites meditate on the 22 cards of the Major Arcana of the Tarot during the Thelemic "holy season" (March 20 - April 10). This essay provides some recommendations for those undertaking these meditations.

  • "Intoning the Collects" - Liber XV instructs deacons to intone the Collects in the Gnostic Mass. What does this mean, and how can it be done well?

  • "The 'Deacon Speech'" - Most celebrations of the Gnostic Mass are preceded by an introductory speech by the deacon. Here are some tips for what to include (and more importantly, what not to include) in the "deacon speech".

Audio and video

The YouTube playlist "Catherine Berry on Thelema and magick" aggregates several of my presentations and seminars. More of these have been recorded, but not yet edited and published; I will add them to the playlist as they become available.

Astronomology sources

My "Astronomology" class covers the basics of astronomy and astrology, and the connections between them. Here are some suggested books on both topics.



Other useful links

  • Two online versions of Liber XV are especially recommended. This version is useful for study, reference, and memorization. The T Helena and T Apiryon annotated version is ideal for those engaged in deeper study of the Mass. Neither of these versions of Liber XV are officially approved editions; those are listed in the EGC Manual, linked below. Therefore, anyone requiring an authoritative source should consult one of the approved editions instead. Nonetheless, these online versions are quite accurate and very convenient.

  • Bishop T Polyphilus has an excellent site filled with essays, rituals, and more, much of it relevant to the Mass. Exploring that material is very highly recommended.

  • The EGC Manual for U.S. Grand Lodge is available as a PDF document. All EGC clergy (novice and ordained) should read it completely at least once a year so that they will be familiar with our policies.