Gregory the Great — on Ezek 2:6 (Homilies on Ezekiel, Book 1, Homily 9)

“"Do not fear their words, and do not dread their faces, because it is a rebellious house." The good are to be feared lest they be offended, lest perchance through them He who always dwells in their hearts be provoked to wrath. For, as was said above, if we offend the wicked, we ought not to fear at all, since our action displeases those whom the justice of the Creator does not please either. What then is to be feared if those are ungrateful to us who are not lovable to God? Hence it is rightly said now: "Fear not their words, and dread not their faces, because it is a provoking house." As if it were openly said: They would be to be feared, unless they provoked me by their actions.”