“If there was originally a Great Thanksgiving in the Communion liturgy, why was it addressed to but two Persons of the Trinity?  If the liturgy was originally framed after the form of a Great Thanksgiving, then what is to prevent one from thinking of the Preface as a part of it?  This startling conjecture, if it be true, would complete a Trinitarian hymn of thanksgiving in the midst of the liturgy.  It would mean that the part which we call the Preface is not a bridge between the Missa Catechumenorum and the Missa Fidelium.  The Preface would then become a great thanksgiving to God the Father, for the creation and preservation of the world, and for the gift of His only begotten Son.  The so-called Canon, when shorn of all that suggests sacrifice, would become a grand hymn of adoration and thanksgiving to the Son of God for the gift of Redemption, and for its application to mankind.  The Epiclesis, so long misunderstood and lost by the Western liturgies, would become a thanksgiving to the Holy Ghost for His sanctifying work, and a prayer that we too may be sanctified, and that the Holy Sacrament may become a Means of Grace to us also.  We are fully mindful of the danger that lurks in such a theory, but we cannot shirk the duty of discussing this theory.”

F.R. Webber, Studies in the Liturgy. 1938, Erie, Pennsylvania: Ashby Printing Company. 163-164.

Image:  Scutum Fidei, c. 1210.  From Cotton Faustina manuscript B. VII, folio 42v.  Compendium Historiae in Genealogia Christi.  From Wikipedia.com, image in public domain.