Whether the aforesaid expressions are true?

❌ Objection 1 : It seems that the aforesaid expressions are not true. Because when we say: "This is My body," the word "this" designates a substance. But according to what was said above (Articles [1],4, ad 3; Question [75], Articles [2],7), when the pronoun "this" is spoken, the substance of the bread is still there, because the transubstantiation takes place in the last instant of pronouncing the words. But it is false to say: "Bread is Christ's body." Consequently this expression, "This is My body," is false.

❌ Objection 2 : Further, the pronoun "this" appeals to the senses. But the sensible species in this sacrament are neither Christ's body nor even its accidents. Therefore this expression, "This is My body," cannot be true.

❌ Objection 3 : Further, as was observed above (Article [4], ad 3), these words, by their signification, effect the change of the bread into the body of Christ. But an effective cause is understood as preceding its effect. Therefore the meaning of these words is understood as preceding the change of the bread into the body of Christ. But previous to the change this expression, "This is My body," is false. Therefore the expression is to be judged as false simply; and the same reason holds good of the other phrase: "This is the chalice of My blood," etc.