In his subsection on the sacraments, “Communion with the Mystical Body” (Catholicism 93 – 101), de Lubac explains the historical understanding of the “threefold manner of the body of Christ:”

When, with St. Augustine, [our ancient forbears] heard Christ say to them: “I am your food, but instead of my being changed into you, it is you who shall be transformed into me,” they unhesitatingly understood that by their reception of the Eucharist they would be incorporated the more in the Church. They could see a profound identity between the mysteries of the “real presence” and of the “mystical body.” And this identity was taken for granted in all their – frequently lively – discussions on the question of the corpus triforme or the triplex modus corporis Christi.”

The three forms of the body of Christ, as de Lubac describes them, are:

• the soma typicon (coined by Origen, the “typical” body, ie, the individual body of the man Jesus),
• the corpus mysticum (the mystical body, which, as William Cavanaugh in Torture and Eucharist and others elsewhere point out, and which de Lubac confirms, originally referred to the eucharistic body, ie, the communion bread, but then was later exalted to refer to the corpus Christi quod est Ecclesia, the body of Christ which is the church),
• the corpus verum (the true body, which originally referred to the body of Christ which is the church, but then was demoted to refer to the communion bread).