This book is my third on topics concerning the Gnostic Catholic Church of O.T.O. In the others, I have been at pains not to publish yet another edition of Liber XV, the canon of the Gnostic Mass. In this case, however, I have included one as a structural basis for a "performance commentary" of the sort offered by Jim and Nancy Wasserman in To Perfect This Feast, and which is also present as a component of Sabazius' Mystery of Mystery. I wasn't motivated by disagreement with those earlier commentaries (although they aren't in lockstep with each other, and I sometimes do differ with one or the other), but I think readers will find that my emphasis and tone are different. I share visualizations and mnemonics, in addition to technical discussions of speech and gesture, and a distinct understanding of the temple configuration.

Most of the book, however, is concerned with the responsibilities of the different ritual officers taken as a whole. It includes a full revision of my earlier work Advice for Deacons, long circulated in digital format, along with separate chapters on the child officers and the priestess and priest. These latter are especially concerned with the notion of "sacrifice" as enacted in the Mass. Naturally, I also direct priests and priestesses to the long section on the Mass in my previous book Fire in the Reed. The material here does not repeat that content.

The final chapter of A Bishop's Advice concerns "Low Mass," which is to say modifications of the Gnostic Mass in the absence of a congregation and perhaps without the sanction of O.T.O. I hope that this will be useful practical information for aspiring officers who are bootstrapping their way into proficiency with the ritual, while honoring their desires to perform it rightly with joy and beauty. It may also be apposite for those working under pandemic emergency conditions that prohibit the convening of a congregation to celebrate Mass.