Isa 66:10

“Those who write of the nature of animals say that all wild creatures, beasts of burden, and sheep and birds have an innate affection for their offspring and young but that the greatest love is found among eagles, who build their nests in very high and inaccessible locations so that no serpent can harm their chicks. Also to be found among newly hatched eagles is the aetiten stone, which overcomes all poisons. If this is true, then the eagle's affection is rightly compared with that of God for his creatures, who protects his children by taking every precaution to shatter the adversary's plots on the name of the stone that is placed in Zion's foundation, lest the dragon and ancient serpent, the devil and Satan, seize his newborns. And this Jerusalem, a mother by whom sons are consoled and caressed on her knees, is she of whom the apostle wrote: "But the Jerusalem above, who is the mother of us all, is free."”

“(Verse 10.) Rejoice with Jerusalem, and be glad for her, all you who love her. Delight in her with joy, all you who mourn over her, so that you may nurse and be satisfied from her comforting breast, and drink deeply and enjoy the abundance of her glory. LXX: Rejoice, O Jerusalem, and gather together all you who love her. Delight in her with joy, all you who mourn over her, so that you may nurse and be filled from her comforting breast, and after you have nursed, be delighted by the entrance of her glory. The apostles are commanded, and the apostolic men, who love both Jerusalems, and the one that has fallen they mourn and lament, and the one that will rise again they eagerly await with all desire, so that they may rejoice with her and in her, the one that is built with living stones, which roll upon the earth, and in the likeness of the wheels of the Cherubim, they follow the preceding spirit: not in those who have been dissolved into eternal ashes. About which the Lord spoke: Amen, amen I say to you, not one stone will remain upon another, until all these things are accomplished (Matthew 24:2). Rejoice, He says, with joy, all you who mourn for her. As we have taught about Peter and Paul, the apostles, and all who were awaiting the redemption of Israel, in order to suckle and be filled with the breasts of her consolation. For it could not be that she who gave birth to a male and was a mother, lacked an abundance of milk for the raising of her people and infants, who were born together, so that she would offer them two breasts, not at all like before in Egypt, broken and lying down, but whole and standing in virgin beauty, of the old and new Instrument, to offer rational milk. About whom the bridegroom speaks to her: Your breasts are better than wine (Song of Solomon 1:1). These were the ones about whom it was specifically said: Blessed are those who mourn, for they will be comforted (Matthew 5:5). And it should be noted that those who are little children are in need of milk for consolation, and they are still in a mortal place. But those who have progressed from the milk of consolation to solid food will have abundant delights of truth and knowledge of all glory, which is called Ziz in Hebrew. For this reason, where in our and the Greek codices it is read μόνιος ἄγριος, that is, singular wild, in Hebrew it is written Ziz Sadai, which Aquila translated as παντόδαπον χώρας, that is, various kinds of regions, to signify that Israel was devastated not only by the Romans, but by all nations. However, the glorious entrance of the Church is to be understood, about which the apostle John writes: 'And the twelve gates were twelve pearls, and the streets of the city were pure gold, as transparent glass' (Rev. 21:21). These pearls are forbidden by the Lord to be thrown before swine (Matt. 7), which the good merchant, when he found them in the Prophets and the Apostles, goes to one most precious pearl, not rejecting the others, but seeking through them something more precious (Matt. 13).”

“Second, he promises immense comfort to the gathered Jews. And first, he invites others to congratulation: rejoice with Jerusalem, and be glad with her, as in the object of joy, setting out the condition of congratulation as to affection: all you that love her: eat, O friends, and drink, and be inebriated, my dearly beloved (Song 5:1); as to the sign of affection: all you that mourn for her: blessed are they that mourn: for they shall be comforted (Matt 5:5).”