The document provides an overview of the history and structure of the Catholic Mass. It discusses how the Mass parallels elements of a courtroom and traces its origins back to Melchizedek and before the Last Supper. The key parts of the Mass are outlined, including the introductory rite, liturgy of the Word, and liturgy of the Eucharist. The Eucharist is described as the highest point where heaven and earth meet, so awe-inspiring that not even angels dare touch it. The document stresses that the Mass is meant to change participants, not the other way around.