Verses 21, 22. — Acquiesce therefore to him, and have peace, and by these things thou shalt have the best fruits. Receive the law from his mouth, and lay up his words in thy heart. The pride and presumption of heretics. — It is a fault of pride to teach one who is better — a thing which heretics often commit, who presume, as it were, to teach Catholics concerning the things they wrongly hold. For they then think that men acquiesce to God, if they happen to consent to their own perversities. And to those who acquiesce they promise peace, because they cease at last to wrangle against those who consent to them. And they promise the best fruits to those who agree with them, because they reckon those alone to do good works whom they exult to draw over to their own dogmas.
To these also this fits, which he adds: Receive the law from his mouth. Because they suspect that the things they themselves hold proceed from the mouth of God: And lay up his words in thy heart. As if he plainly asserted, saying: The words which up to now thou hast held on thy lips and not in thy heart. For because he rejects their perverse dogmas, they charge that he has held the words of God not in his understanding, but only in outward show. Hence, as if under a certain guise of sweetness, they pour in the venom of a pestilential persuasion, so that they may admonish the Church to lay up the words of God in her heart. But if these had ever departed from her heart, she would by no means hear such things from them. There follows: