Chapter 15 — Part II: The Sacraments — Introduction on the Sacraments in General
Section 38. In this the Sacraments of the New Law excel those of the Old that, as far as we know, there was no definite form of administering the latter, and hence they were very uncertain and obscure. In our Sacraments, on the contrary, the form is so definite that any, even a casual deviation from it renders the Sacrament null. Hence the form is expressed in the clearest terms, such as exclude the possibility of doubt.