George Leo Haydock

The apostle had been obliged, in different parts of his first epistle, to say some things to his own advantage, in order to maintain the dignity of his ministry against false teachers, who had endeavoured to lessen his authority. He is again obliged to shew the excellency of his ministry, and the superiority of the gospel over the law of Moses. (Theodoret) — We have not need, he says, of commendatory letters, like those false teachers: we have only to say that we founded the Church of Corinth, and we shall be sufficiently known. Your religion, your piety, and your virtues are renowned in the whole world. (ver. 2.) This is our letter: we have no need to speak: the effects speak for themselves. But still this is not our doing; for we are not sufficient to think any thing of ourselves. (ver. 5.) This letter is not of our writing; we could only do the same as Moses in the old law, prepare the tables, (ministered by us) it was God himself that wrote the ten commandments, and it is God himself that has written this our letter, by implanting his faith in your hearts. (Calmet)