<p>2021 Reprint of the 1963 Edition.&nbsp;Full facsimile of the original edition and not reproduced with Optical Recognition Software.&nbsp;Since Vatican II the Catholic church has encouraged a more active and enlightened participation by the faithful in offering the Mass.&nbsp;But a grasp of the theology behind the liturgy makes that participation more meaningful.&nbsp;This book is a contribution in this area.</p>