Ps 81:5

“And again that darkness is brought upon men by their evil deeds, we learn from John himself, when he says in his epistle, "If we say that we have fellowship with Him and walk in darkness, we lie and do not the truth," and again, "He that saith he is in the light, and hateth his brother, is in darkness even until now," and again, "He that hateth his brother is in darkness, and walketh in darkness, and knoweth not whither he goeth, because darkness hath blinded his eyes." Walking in darkness signifies evil conduct, and to hate one's brother, is not that to fall away from that which is properly called knowledge? But he also who is ignorant of divine things walks in darkness, just because of that ignorance; as David says, "They knew not, they understood not, they walk in darkness."”

“To all of them, verily, what follows is most fitly suited: "They did not know nor understand, they walk on in darkness." "For if even they had known, they would never have crucified the Lord of glory:" and those others, if they had known, would never have consented to ask that Barabbas should be freed, and Christ should be crucified. But as the above-mentioned blindness happened in part unto Israel until the fulness of the Gentiles should come in, this blindness of that People having caused the crucifixion of Christ, "all the foundations of the earth shall be moved." So have they been moved, and shall they be moved, until the predestined fulness of the Gentiles shall come in. For at the actual death of the Lord the earth was moved, and the rocks rent. And if we understand by the foundations of the earth those who are rich in the abundance of earthly possessions, it was truly foretold that they should be moved, either by wondering that lowliness, poverty, death, should be so loved and honoured in Christ, when it is to their mind great misery; or even in that themselves should love and follow it, and set at nought the vain happiness of this world. So are all the foundations of the earth moved, while they partly admire, and partly are even altered. For as without absurdity we call foundations of heaven those on whom the kingdom of heaven is built up in the persons of saints and faithful; whose first foundation is Christ Himself, born of the Virgin, of whom the Apostle says, "Other foundation can no man lay than that which is laid, which is Christ Jesus;" next the Apostles and Prophets themselves, by whose authority the heavenly place is chosen, that by obeying them we may be builded together with them; whence he says to the Ephesians, "Ye are built upon the foundation of Apostles and Prophets, Christ Jesus Himself being the chief corner stone." ...But the kingdom of earthly happiness is pride, to oppose which came the lowliness of Christ, rebuking those whom He wished by lowliness to make the children of the Most High, and blaming them...”

“Where sacred Scripture is lacking, it is necessary that the earth, that is, the Church, be shaken: "They neither knew nor understood, they walk in darkness; all the foundations of the earth shall be moved." Arius, who wished to take away the foundation of the Trinity; Nestorius, who wished to destroy the unity of person; and Eutyches, who wished to confuse the natures in Christ: these men shook the foundations of the Church.”