The Mysteries of Christianity

Late German scholar, Fr. Matthias Joseph Scheeben's greatest work, The Secrets of Christianity, with over 800 pages, is a rigorous and spiritually profound theology. In it, he investigates the comprehensibility and interconnectedness of Christianity's supernatural mysteries, finally showing that Christian theology is a science in the eyes of human reason, even if its topic is beyond human knowledge.

To do this, Scheeben examines nine key Christian mysteries—the Trinity, creation, sin, the Incarnation, the Eucharist, the Church and her sacraments, justification, eschatological glory, and predestination—in an effort to give a cohesive perspective of the whole spectrum of revealed truth. Scheeben starts with the Trinity as the source of the supernatural order, demonstrating how the everlasting processions of persons in God—the Father's begetting of the Son and the spiration of the Spirit being in different ways—form the basis of the salvific economy, and are the cause of grace in the soul. The Incarnation and the bestowal of grace by the Son and the Spirit pave the way for people to experience the beatific vision and therefore fulfil the purpose for which God created them.

Scheeben places special emphasis on the Eucharist as a way of reconciliation with God because to its intimate link with the mystery of the Incarnation. Putting his understanding of the Eucharist ahead of the Church's, he indicates that his is a really Eucharistic ecclesiology, focusing on the eternal presence of the incarnate divine Son.

Pope Pius XI encouraged study of the theologian’s works, reflecting: “The entire theology of Scheeben bears the stamp of a pious ascetical theology.”