Catena Aurea on John 1:16–17: Augustine of Hippo

But what have ye received? Grace for grace. So that we are to understand that we have received a certain something from His fulness, and over and above this, grace for grace; that we have first received of His fulness, first grace; and again, we have received grace for grace. What grace did we first receive? Faith: which is called grace, because it is given freely3. This is the first grace then which the sinner receives, the remission of his sins. Again, we have grace for grace; i. e. in stead of that grace in which we live by faith, we are to receive another, viz. life eternal: for life eternal is as it were the wages of faith. And thus as faith itself is a good grace, so life eternal is grace for grace. There was not grace in the Old Testament; for the law threatened, but assisted not, commanded, but healed not, shewed our weakness, but relieved it not. It prepared the way however for a Physician who was about to come, with the gifts of grace and truth: whence the sentence which follows: For the law was given by Moses, but grace and truth were made by Jesus Christ. The death of thy Lord hath destroyed death, both temporal and eternal; that is the grace which was promised, but not contained, in the law.