The new title of the book, which was first published in 2008 under the title "A Concise History of the Christian Church," aims to show that all phenomena that, while having some direct relationship with Jesus Christ, do not constitute a complete part of the Church but influence it, such as Gnosticism, ecstatic phenomena, etc.

This book attempts to present the history of the Christian Church during the first millennium of its earthly existence, where its ending coincides with the Great Schism of East and West. The purpose of this work is to provide a guiding thread while simultaneously allowing the reader to continue their research through the relevant literature.

The content of the work is shaped by the author's personal research, as well as his own teaching notes from his teaching work at the Higher Ecclesiastical School (now the Higher Ecclesiastical Academy of Athens). The reader, upon reading, may notice that many things are presented elliptically or summarizingly, precisely to keep the entire structure of the discussion concise, a fact that does not preclude the future completion of the work after critical feedback from the reading audience.