Title II: On the Most Holy Sacrament of the Eucharist

— Utility. While we are preparing to speak about the Sacrament of the Most Holy Eucharist, which is deservedly called the sacrament of sacraments, it has seemed good to us first to gather the utility of the argument from its very nobility. It pleases us to set forth this excellence in the words of the Council of Trent, sess. XIII, ch. 3, and of St. Thomas, who throughout his treatises can be called the Doctor, and by his hymns the Singer, of the Most Holy Eucharist.

"This indeed is common to the Most Holy Eucharist with the other sacraments, that it is a symbol of a sacred thing and a visible form of invisible grace; but this excellent and singular thing is found in it, that the other sacraments first have the power of sanctifying when someone uses them, but in the Eucharist the author of sanctity himself is present before use" (Trent).

"This sacrament of itself has power to confer grace" (3 p., q. 79, art. 1, ad 1). "The effect which the passion of Christ made in the world, this sacrament makes in man" (ibid., c.). "Simply speaking, the sacrament of the Eucharist is the chief among the other sacraments. And this appears in three ways: first, from that which is contained in it; for in the sacrament of the Eucharist Christ himself is contained substantially, but in the other sacraments there is contained a certain instrumental power participated from Christ... Secondly, this appears from the order of the sacraments to one another; for all the other sacraments seem to be ordered to this sacrament as to an end. For it is manifest that the sacrament of Order is ordered to the consecration of the Eucharist; but the sacrament of Baptism is ordered to the reception of the Eucharist, in which one is also perfected by Confirmation, so that he may not be afraid to withdraw himself from such a sacrament; by Penance also and Extreme Unction man is prepared for worthily receiving the body of Christ; Matrimony also, at least by its signification, touches this sacrament, inasmuch as it signifies the conjunction of Christ and the Church, whose unity is figured by the sacrament of the Eucharist... Thirdly, this appears from the rite of the sacraments. For nearly all the sacraments are consummated in the Eucharist, as is clear from the fact that the ordained communicate, and also the baptized, if they are adults" (3 p., q. 65, art. 3, c.).

If then we turn directly to considering practical utility, through a prudent manner of counseling the use of the sacrament the confessor will be able greatly to preserve, strengthen, and restore the virtue of the penitent. Therefore, as priest he must draw from the present part of the treatise rules concerning licit administration, and as spiritual physician counsels concerning the use of this sacrament.

— Appendix IX belongs to this section. Historical Matters Concerning the Sacrament of the Most Holy Eucharist. Cf. Appendix IX.