http://sedevacantist.com/newmass/qtvjmcn.htm8) WHAT IS MEANT BY "THE REALITY" OF A SACRAMENT?
87. Earlier in this monograph this quotation of St. Thomas was cited, "Some heretics in conferring sacraments do not observe the form prescribed by the Church: and these confer neither the sacrament nor the reality of the sacrament." What does the Angelic Doctor mean by "the reality" of a sacrament? For a clear understanding of what is to follow in this monograph, it is imperative that this fundamental concept - that is, "the reality" of a sacrament - be grasped.
Three Distinct Elements in a Sacrament
88. In the sacraments there are three distinct elements that must be regarded. (1) There is the element which is sacrament only; that is, the outward sign, or matter and form, considered by itself. In other words, the external rite of the sacrament. (2) Next there is the reality of the sacrament - this is what St. Thomas calls "res sacramenti" -; and by this is meant the crowning effect or principal fruit of the sacrament. In other words, "the reality" of the sacrament is the grace proper to the particular sacrament. It is that which is signified by the external rite, which is that which signifies. And (3) there is the element which contains something of both the first two elements; that is, it contains something of the sacrament and something of the reality. This element we call "the reality and the sign." Consequently, it follows that this element both signifies and is signified.
Baptism As An Example
89. A clear insight into the meaning of the preceding paragraph can be gained by considering the Sacrament of Baptism as an example. (1) In Baptism the element which is sacrament only is the outward sign, namely, the pouring of the water. That is to say, the water and the washing, coupled, of course, with the recitation of the proper words which constitute the form of this sacrament. It is this element which does the signifying.
90. And (2) there is the element which is the reality only; that is, the chief fruit or grace proper to the Sacrament of Baptism. This crowning effect is the washing away of original sin (and, in the case of adults, actual sin also). In the words of St. Thomas, this chief effect - the reality of this sacrament - is "inward justification." This inward justification can be lost. It is clear, then, that "the reality" is the element which is signified.
91. And, finally, (3) the element which is both sacrament and reality, sometimes called "the reality and the sign, is the Baptismal character imprinted on the soul. This character cannot be lost; it is indelible. It must be noted that this third element both signifies and is signified. First of all, it signifies (or is the sign of) the aforesaid inward justification. And, lastly, it is signified by the aforesaid outward washing.