In his great work
The Idea of a University of 1852, John Henry Newman at one point turns aside from his main point to explain the difference between a minister of the sacraments and a preacher:
In this respect the preacher differs from the minister of the sacraments, that he comes to his hearers, in some sense or other, with antecedents.
Clad in his sacerdotal vestments, he [the minister of sacraments] sinks what is individual in himself altogether, and is but the representative of Him from whom he derives his commission. His words, his tones, his actions, his presence, lose their personality; one bishop, one priest, is like another; they all chant the same notes, and observe the same genuflexions, as they give one peace and one blessing, as they offer one and the same sacrifice. The Mass must not be said without a Missal under the priest’s eye; nor in any language but that in which it has come down to us from the early hierarchs of the Western Church.