Full of grace and truth. Of this the meaning is twofold. For it may be understood of the Humanity, and the Divinity of the Incarnate Word, so that the fulness of grace has reference to the Humanity, according to which Christ is the Head of the Church, and the first-born of every creature: for the greatest and original example of grace, by which man, with no preceding merits, is made God, is manifested primarily in Him. The fulness of the grace of Christ may also be understood of the Holy Spirit, whose sevenfold operation filled Christ’s Humanity. (Is. 11:2) The fulness of truth applies to the Divinity … But if you had rather understand the fulness of grace and truth of the New Testament, you may with propriety pronounce the fulness of the grace of the New Testament to be given by Christ, and the truth of the legal types to have been fulfilled in Him.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Hom. 2