Objection 1: It seems that two ways ought not to be distinguished of eating Christ's body, namely, sacramentally and spiritually. For, as Baptism is spiritual regeneration, according to John 3:5: "Unless a man be born again of water and the Holy Ghost," etc., so also this sacrament is spiritual food: hence our Lord, speaking of this sacrament, says (John 6:64): "The words that I have spoken to you are spirit and life." But there are no two distinct ways of receiving Baptism, namely, sacramentally and spiritually. Therefore neither ought this distinction to be made regarding this sacrament.
Obj. 2: Further, when two things are so related that one is on account of the other, they should not be put in contradistinction to one another, because the one derives its species from the other. But sacramental eating is ordained for spiritual eating as its end. Therefore sacramental eating ought not to be divided in contrast with spiritual eating.
Obj. 3: Further, things which cannot exist without one another ought not to be divided in contrast with each other. But it seems that no one can eat spiritually without eating sacramentally; otherwise the fathers of old would have eaten this sacrament spiritually. Moreover, sacramental eating would be to no purpose, if the spiritual eating could be had without it. Therefore it is not right to distinguish a twofold eating, namely, sacramental and spiritual.
On the contrary, The gloss says on 1 Cor. 11:29: "He that eateth and drinketh unworthily," etc.: "We hold that there are two ways of eating, the one sacramental, and the other spiritual."
I answer that, There are two things to be considered in the receiving of this sacrament, namely, the sacrament itself, and its fruits, and we have already spoken of both (QQ. 73, 79). The perfect way, then, of receiving this sacrament is when one takes it so as to partake of its effect. Now, as was stated above (Q. 79, AA. 3, 8), it sometimes happens that a man is hindered from receiving the effect of this sacrament; and such receiving of this sacrament is an imperfect one. Therefore, as the perfect is divided against the imperfect, so sacramental eating, whereby the sacrament only is received without its effect, is divided against spiritual eating, by which one receives the effect of this sacrament, whereby a man is spiritually united with Christ through faith and charity.
Reply Obj. 1: The same distinction is made regarding Baptism and the other sacraments: for, some receive the sacrament only, while others receive the sacrament and the reality of the sacrament. However, there is a difference, because, since the other sacraments are accomplished in the use of the matter, the receiving of the sacrament is the actual perfection of the sacrament; whereas this sacrament is accomplished in the consecration of the matter: and consequently both uses follow the sacrament. On the other hand, in Baptism and in the other sacraments that imprint a character, they who receive the sacrament receive some spiritual effect, that is, the character. which is not the case in this sacrament. And therefore, in this sacrament, rather than in Baptism, the sacramental use is distinguished from the spiritual use.
Reply Obj. 2: That sacramental eating which is also a spiritual eating is not divided in contrast with spiritual eating, but is included under it; but that sacramental eating which does not secure the effect, is divided in contrast with spiritual eating; just as the imperfect, which does not attain the perfection of its species, is divided in contrast with the perfect.
Reply Obj. 3: As stated above (Q. 73, A. 3), the effect of the sacrament can be secured by every man if he receive it in desire, though not in reality. Consequently, just as some are baptized with the Baptism of desire, through their desire of baptism, before being baptized in the Baptism of water; so likewise some eat this sacrament spiritually ere they receive it sacramentally. Now this happens in two ways. First of all, from desire of receiving the sacrament itself, and thus are said to be baptized, and to eat spiritually, and not sacramentally, they who desire to receive these sacraments since they have been instituted. Secondly, by a figure: thus the Apostle says (1 Cor. 10:2), that the fathers of old were "baptized in the cloud and in the sea," and that "they did eat . . . spiritual food, and . . . drank . . . spiritual drink." Nevertheless sacramental eating is not without avail, because the actual receiving of the sacrament produces more fully the effect of the sacrament than does the desire thereof, as stated above of Baptism (Q. 69, A. 4, ad 2).