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.
Source: Homilies on the First Epistle of John (New Advent)