3 When we say to them, If you be Catholic Christians, communicate with that Church from which the Gospel is spread abroad over the whole earth: communicate with that Jerusalem: when this we say to them, they make answer to us, we do not communicate with that city where our King was slain, where our Lord was slain: as though they hate the city where our Lord was slain. The Jews slew Him whom they found on earth, these scorn Him that sits in heaven! Which are the worse; those who despised Him because they thought Him man, or those who scorn the sacraments of Him whom now they confess to be God? But they hate, forsooth, the city in which their Lord was slain! Pious men, and merciful! They much grieve that Christ was slain, and in men they slay Christ! But He loved that city, and pitied it: from it He bade the preaching of Him begin, “beginning at Jerusalem.” He made there the beginning of the preaching of His name: and you shrink back with horror from having communion with that city! No marvel that being cut off you hate the root. What said He to His disciples? “Sit still in the city, because I send my promise upon you.” Behold what the city is that they hate! Haply they would love it, if Christ's murderers dwelt in it. For it is manifest that all Christ's murderers, i.e., the Jews, are expelled from that city. That which had in it them that were fierce against Christ, has now them that adore Christ. Therefore do these men hate it, because Christians are in it. There was it His will that His disciples should tarry, and there that He should send to them the Holy Ghost. Where had the Church its commencement, but where the Holy Ghost came from heaven, and filled the hundred and twenty sitting in one place? That number twelve was made tenfold. They sat, an hundred and twenty persons, and the Holy Ghost came, “and filled the whole place, and there came a sound, as it were the rushing of a mighty wind, and there were cloven tongues like as of fire.” You have heard the Acts of the Apostles: this was the lesson read today: “They began to speak with tongues as the Spirit gave them utterance.” And all who were on the spot, Jews who had come from various nations, recognised each his own tongue, and marvelled that those unlearned and ignorant men had on the sudden learned not one or two tongues, but the tongues of all nations whatsoever. There, then, where all tongues sounded, there was it betokened that all tongues should believe. But these men, who much love Christ, and therefore refuse to communicate with the city which killed Christ, so honor Christ as to affirm that He is left to two tongues, the Latin and the Punic, i.e. African. Christ possess only two tongues! For there are but these two tongues on the side of Donatus, more they have not. Let us awake, my brethren, let us rather see the gift of the Spirit of God, and let us believe the things spoken before concerning Him, and let us see fulfilled the things spoken before in the Psalm: “There are neither speeches nor discourses, but their voices are heard among them.” And lest haply the case be so that the tongues themselves came to one place, and not rather that the gift of Christ came to all tongues, hear what follows: “Into all the earth is their sound gone out, and unto the ends of the world their words.” Wherefore this? Because “in the sun has He set His tabernacle,” i.e., in the open light. His tabernacle, His flesh: His tabernacle, His Church: “in the sun” it is set; not in the night, but in the day. But why do those not acknowledge it? Return to the lesson at the place where it ended yesterday, and see why they do not acknowledge it: “He that hates his brother, walks in darkness, and knows not whither he goes, because the darkness has blinded his eyes.” For us then, let us see what follows, and not be in darkness. How shall we not be in darkness? If we love the brethren. How is it proved that we love the brotherhood? By this, that we do not rend unity, that we hold fast charity.
4. “I write unto you, little children, because your sins are forgiven you through His name.” Therefore, “little children,” because in forgiveness of sins you have your birth. But through whose name are sins forgiven? Through Augustine's? No, therefore neither through the name of Donatus. Be it your concern to see who is Augustine, or who Donatus: no, not through the name of Paul, not through the name of Peter. For to them that divided unto themselves the Church, and out of unity essayed to make parties, the mother charity in the apostle travailing in birth with her little ones, exposes her own bowels, with words does as it were rend her breasts, bewails her children whom she sees borne out dead, recalls unto the one Name them that would needs make them many names, repels them from the love of her that Christ may be loved, and says, “Was Paul crucified for you? Or were you baptized in the name of Paul?” What says he? “I would not that you be mine, that so you may be with me: be with me; all we are His who died for us, who was crucified for us”: whence here also it is said, “Your sins are forgiven you through His name,” not through the name of any man.
5. “I write unto you, fathers.” Why first sons? “Because your sins are forgiven you through His name,” and you are regenerated into a new life, therefore sons. Why fathers? “Because you have known Him that is from the beginning:” for the beginning has relation unto fatherhood. Christ new in flesh, but ancient in Godhead. How ancient think we? How many years old? Think we, of greater age than His mother? Assuredly of greater age than His mother, for “all things were made by Him.” If all things, then did the Ancient make the very mother of whom the New should be born. Was He, think we, before His mother only? Yea, and before His mother's ancestors is His antiquity. The ancestor of His mother was Abraham; and the Lord says, “Before Abraham I am.” Before Abraham, say we? The heaven and earth, ere man was, were made. Before these was the Lord, nay rather also is. For right well He says, not, Before Abraham I was, but, “Before Abraham I Am.” For that of which one says, “was,” is not; and that of which one says, “will be,” is not yet: He knows not other than to be. As God, He knows “to be:” “was,” and “will be,” He knows not. It is one day there, but a day that is for ever and ever. That day yesterday and tomorrow do not set in the midst between them: for when the 'yesterday' is ended, the 'today' begins, to be finished by the coming 'tomorrow.' That one day there is a day without darkness, without night, without spaces, without measure, without hours. Call it what you will: if you will, it is a day; if you will, a year; if you will, years. For it is said of this same, “And your years shall not fail.” But when is it called a day? When it is said to the Lord, “Today have I begotten You.” From the eternal Father begotten, from eternity begotten, in eternity begotten: with no beginning, no bound, no space of breadth; because He is what is, because Himself is “He that Is.” This His name He told to Moses: “You shall say unto them, He that Is has sent me unto you.” Why speak then of “before Abraham”? Why, before Noe? Why, before Adam? Hear the Scripture: “Before the day-star have I begotten You.” In fine, before heaven and earth. Wherefore? Because “all things were made by Him, and without Him was nothing made.” By this you know the “fathers:” for they become fathers by acknowledging “That which is from the beginning.”
Source: Homilies on the First Epistle of John (New Advent)