2 For if either of these be lacking, the remaining one becomes useless, owing to its divorce from the other, for if a preacher be indifferent to praise, and yet cannot produce the doctrine “which is with grace seasoned with salt,” he becomes despised by the multitude, while he gains nothing from his own nobleness of mind; and if on the other hand he is successful as a preacher, and is overcome by the thought of applause, harm is equally done in turn, both to himself and the multitude, because in his desire for praise he is careful to speak rather with a view to please than to profit. And as he who neither lets good opinion influence him, nor is skillful in speaking, does not yield to the pleasure of the multitude, and is unable to do them any good worth mentioning, because he has nothing to say, so he who is carried away with desire for praise, though he is able to render the multitude better service, rather provides in place of this such food as will suit their taste, because he purchases thereby the tumult of acclamation.
Source: On the Priesthood (New Advent)