And these things write we unto you,.... Concerning the deity and eternity of Christ, the Word and concerning the truth of his humanity, and the manifestation of him in the flesh; and concerning that eternal life and salvation which is declared in the Gospel to be in him; and concerning the saints' fellowship one with another, and with God the Father, and with Jesus Christ:that your joy may be full; meaning either their spiritual joy in this life, which has Christ for its object, and is increased by the consideration of his proper deity, his incarnation and mediation by a view of free justification by his righteousness, and atonement by his blood; by a sight of his glorious person by faith, and by intimate communion with him, and a discovery of his love, which passeth knowledge: and which joy, when it is large, and very great, may, in a comparative sense, be said to be full, though not absolutely so, and being as much as can well be enjoyed in this state; and nothing can more contribute to it than a declaration of the above things in the Gospel, and an experimental acquaintance with them, and enjoyment of them: or else it may intend the joy of the saints in the world to come, in the presence of Christ, where are fulness of joy, and pleasures for evermore; and so may express the ultimate glory and happiness of God's people, which is the chief end, as of his purposes, promises, and covenant, so of the Gospel, and the declaration of it.
The Syriac version renders it, "that our joy, which is in you, may be full"; it is the joy of the ministers of the word, when the saints are established in the faith of Christ's person and offices, and have communion with him, with which view they declare him, and bear record of him.