13 “For You are great, and doing wondrous things: You alone are the great God”. Let no man call himself great. Some were to be who would call themselves great: against these it is said, “You alone are the great God.” For what great thing is ascribed to God, when it is said that He alone is the great God? Who knows not that He is the great God? But because there were to be some who would call themselves great and make God little, against these it is said, “You alone are the great God.”
For what You say is fulfilled, not what those say who call themselves great. What has God said by His Spirit? “All nations.” What says he, whoever he is, who calls himself great? “Far from it: God is not worshipped in all nations: all nations have perished, Africa alone remains.” This you say, who callest yourself great: another thing He says who alone is the great God. What says He, who alone is the great God? “All nations.” I see what the only great God has said: let man be silent, who is falsely great; great only in appearance, because he disdains to be small.
Who disdains to be small? He who says this. Whoever will be great among you, said the Lord, shall be your servant. If that man had wished to be the servant of his brethren, he would not have separated them from their mother: but when he wishes to be great, and wishes not to be small, as would be for his welfare, God, who resists the proud, and gives grace to the humble, because He alone is great, fulfills all things which He predicted, and contradicts those who blaspheme. For such persons blaspheme against Christ, who say that the Church has perished from the whole world, and is left only in Africa.
If you were to say to him, You will lose your villa, he would perhaps scarcely keep from laying his hand upon you: and yet he says, that Christ has lost His inheritance, redeemed by His own Blood! See now what a wrong he does, my brethren. The Scripture says, “In a wide nation is the king's honour; but in the domination of the people is the affliction of a prince.” This wrong then thou dost unto Christ, to say that His people is diminished to that small number. Was it for this you were born, for this you call yourself a Christian, that you may grudge Christ His glory, whose sign you say that you bear on your forehead, and hast lost out of your heart?
In a wide nation is the king's honour: acknowledge your King: give Him glory, give Him a wide nation. What wide nation shall I give Him, do you say? Choose not to give Him from your own heart, and you will give aright. Whence am I to give? You will say. Lo, give from hence: “All nations that You have made shall come and worship before You, O Lord.” Say this, confess this, and you have given a wide nation: for all nations in One are one: this is very oneness. For as there is a Church and Churches, and those are Churches which also are a Church, so that is a nation which was nations: formerly nations, many nations, now one nation.
Why one nation? Because one faith, one hope, one charity, one expectation. Lastly, why not one nation, if one country? Our country is heavenly, our country is Jerusalem: whoever is not a citizen of it, belongs not to that nation: but whoever is a citizen of it is in that one nation of God. And this nation, from the east to the west, from the north and the sea, is extended through the four quarters of the whole world. This God says: From the east and west, from the north and the sea, give glory to God. This He foretold, this He fulfilled, who alone is great. Let him therefore who would not be little cease from saying this against Him who alone is great: for there cannot be two great, God and Donatus.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)