55 As for methods of expounding Holy Scripture - "for amongst the dispensers of the mysteries of God it is required that a man be found faithful" - St. Jerome lays down that we have got to keep to the "true interpretation, and that the real function of a commentator is to set forth not what he himself would like his author to mean, but what he really does mean." And he continues: "It is dangerous to speak in the Church, lest through some faulty interpretation we make Christ's Gospel into man's Gospel." And again: "In explaining the Bible we need no florid oratorical composition, but that learned simplicity which is truth." This ideal he ever kept before him; he acknowledges that in his Commentaries he "seeks no praise, but so to set out what another has well said that it may be understood in the sense in which it was said." He further demands of an expositor of Scripture a style which, "while leaving no impression of haziness. . .yet explains things, sets out the meaning, clears up obscurities, and is not mere verbiage."
Source: Spiritus Paraclitus (Vatican.va)