the consecrated matter belongs to a certain
perfection of the sacrament, in the same way as operation is not the
first but the second perfection of a thing, consequently, the whole
perfection of this sacrament is expressed by all those words: and it
was in this way that Eusebius understood that the sacrament was
accomplished by those words, as to its first and second perfection.

Reply Obj. 3: In the sacrament of Baptism the minister exercises an
act regarding the use of the matter, which is of the essence of the
sacrament: such is not the case in this sacrament; hence there is no
parallel.

Reply Obj. 4: Some have contended that this sacrament cannot be
accomplished by uttering the aforesaid words, while leaving out the
rest, especially the words in the Canon of the Mass. But that this is
false can be seen both from Ambrose's words quoted above, as well as
from the fact that the Canon of the Mass is not the same in all
places or times, but various portions have been introduced by various
people.

Accordingly it must be held that if the priest were to pronounce only
the aforesaid words with the intention of consecrating this
sacrament, this sacrament would be valid because the intention would
cause these words to be understood as spoken in the person of Christ,
even though the words were pronounced without those that precede. The
priest, however, would sin gravely in consecrating the sacrament
thus, as he would not be observing the rite of the Church. Nor does
the comparison with Baptism prove anything; for it is a sacrament of
necessity: whereas the lack of this sacrament can be supplied by the
spiritual partaking thereof, as Augustine says (cf. Q. 73, A. 3, ad
1).
_______________________

SECOND ARTICLE [III, Q. 78, Art. 2]

Whether This Is the Proper Form for the Consecration of the Bread:
"This Is My Body"?

Objection 1: It seems that this is not the proper form of this
sacrament: "This is My body." For the effect of a sacrament ought to
be expressed in its form. But the effect of the consecration of the
bread is the change of the substance of the bread into the body of
Christ, and this is better expressed by the word "becomes" than by
"is." Therefore, in the form of the consecration we ought to say:
"This becomes My body."

Obj. 2: Further, Ambrose says (De Sacram. iv), "Christ's words
consecrate this sacrament. What word of Christ? This word, whereby
all things are made. The Lord commanded, and the hea