From “Tractate 124 on John” 5, 7 (419)
Christ’s words, “I wish him to remain until I come,” should not be taken to imply that John was to remain on earth until Christ’s coming, but rather that he was to wait because it is not now but only when Christ comes that the life he symbolizes will find fulfillment. On the other hand, Christ says to Peter, “Your duty is to follow me,” because the life Peter symbolizes can attain its goal only by action here and now.
Yet we should make no mental separation between these great apostles. Both lived the life symbolized by Peter; both were to attain the life symbolized by John. Symbolically, one followed, the other remained, but living by faith they both endured the sufferings of this present life of sorrow and they both longed for the joys of the future life of happiness.
Nor were they alone in this. They were one with the whole Church, the bride of Christ, which will in time be delivered from the trials of this life and live forever in the joy of the next. These two kinds of life were represented respectively by Peter and John, yet both apostles lived by faith in this present, passing life, and in eternal life both have the joy of vision.
And so for the sake of all the saints inseperably united to the body of Christ, to guide them through the storms of this life, Peter, the chief of the apostles, received the keys of the kingdom of heaven with the power to bind and loose sins; and for the sake of those same saints, to plumb the depths of that other, hidden life, John the evangelist reclined on the breast of Christ.
For it is not only Peter but the whole Church that binds and looses from sin; and as for the sublime teaching of John about the Word, who in the beginning was God with God, and everything else he told us about Christ’s divinity, and about the trinity and unity of the Godhead, which now, until the Lord comes, is all like a faint reflection in a mirror, but which will be seen face to face in the kingdom of heaven — it was not only John who drank in this teaching that came forth from the Lord’s breast as from a fountain. All who belong to the Lord are to drink it in, according to their several capacities, and this is why the Lord himself has spread John’s gospel throughout the world.
St. Augustine (354-430) was a theologian and philosopher who served as Bishop of Hippo Regius in North Africa. He was a voluminous author, whose writings about God’s grace, the Sacraments, and the Church have been profoundly influential in the development of Western Christianity. His Tractates on John are based on a series of exegetical homilies he delivered during his ministry as bishop. His feast day is August 26.