11 Then God says to Cain: "You are cursed from the earth, which has opened its mouth to receive your brother's blood at your hand. For you shall till the earth, and it shall no longer yield unto you its strength. A mourner and an abject shall you be on the earth." It is not, Cursed is the earth, but, Cursed are you from the earth, which has opened its mouth to receive your brother's blood at your hand. So the unbelieving people of the Jews is cursed from the earth, that is, from the Church, which in the confession of sins has opened its mouth to receive the blood shed for the remission of sins by the hand of the people that would not be under grace, but under the law. And this murderer is cursed by the Church; that is, the Church admits and avows the curse pronounced by the apostle: "Whoever are of the works of the law are under the curse of the law." Then, after saying, Cursed are you from the earth, which has opened its mouth to receive your brother's blood at your hand, what follows is not, For you shall till it, but, You shall till the earth, and it shall not yield to you its strength. The earth he is to till is not necessarily the same as that which opened its mouth to receive his brother's blood at his hand. From this earth he is cursed, and so he tills an earth which shall no longer yield to him its strength. That is, the Church admits and avows the Jewish people to be cursed, because after killing Christ they continue to till the ground of an earthly circumcision, an earthly Sabbath, an earthly passover, while the hidden strength or virtue of making known Christ, which this tilling contains, is not yielded to the Jews while they continue in impiety and unbelief, for it is revealed in the New Testament. While they will not turn to God, the veil which is on their minds in reading the Old Testament is not taken away. This veil is taken away only by Christ, who does not do away with the reading of the Old Testament, but with the covering which hides its virtue. So, at the crucifixion of Christ, the veil was rent in two, that by the passion of Christ hidden mysteries might be revealed to believers who turn to Him with a mouth opened in confession to drink His blood. In this way the Jewish people, like Cain, continue tilling the ground, in the carnal observance of the law, which does not yield to them its strength, because they do not perceive in it the grace of Christ. So too, the flesh of Christ was the ground from which by crucifying Him the Jews produced our salvation, for He died for our offenses. But this ground did not yield to them its strength, for they were not justified by the virtue of His resurrection, for He arose again for our justification. As the apostle says: "He was crucified in weakness, but He lives by the power of God." This is the power of that ground which is unknown to the ungodly and unbelieving. When Christ rose, He did not appear to those who had crucified Him. So Cain was not allowed to see the strength of the ground which he tilled to sow his seed in it; as God said, "You shall till the ground, and it shall no longer yield unto you its strength."
12. "Groaning and trembling shall you be on the earth." Here no one can fail to see that in every land where the Jews are scattered they mourn for the loss of their kingdom, and are in terrified subjection to the immensely superior number of Christians. So Cain answered, and said: "My case is worse, if You drive me out this day from the face of the earth, and from Your face shall I be hid, and I shall be a mourner and an outcast on the earth; and it shall be that every one that finds me shall slay me." Here he groans indeed in terror, lest after losing his earthly possession he should suffer the death of the body. This he calls a worse case than that of the ground not yielding to him its strength, or than that of spiritual death. For his mind is carnal; for he thinks little of being hid from the face of God, that is, of being under the anger of God, were it not that he may be found and slain. This is the carnal mind that tills the ground, but does not obtain its strength. To be carnally minded is death; but he, in ignorance of this, mourns for the loss of his earthly possession, and is in terror of bodily death. But what does God reply? "Not so," He says; "but whosoever shall kill Cain, vengeance shall be taken on him sevenfold." That is, It is not as you say, not by bodily death shall the ungodly race of carnal Jews perish. For whoever destroys them in this way shall suffer sevenfold vengeance, that is, shall bring upon himself the sevenfold penalty under which the Jews lie for the crucifixion of Christ. So to the end of the seven days of time, the continued preservation of the Jews will be a proof to believing Christians of the subjection merited by those who, in the pride of their kingdom, put the Lord to death.
13. "And the Lord God set a mark upon Cain, lest any one finding him should slay him." It is a most notable fact, that all the nations subjugated by Rome adopted the heathenish ceremonies of the Roman worship; while the Jewish nation, whether under Pagan or Christian monarchs, has never lost the sign of their law, by which they are distinguished from all other nations and peoples. No emperor or monarch who finds under his government the people with this mark kills them, that is, makes them cease to be Jews, and as Jews to be separate in their observances, and unlike the rest of the world. Only when a Jew comes over to Christ, he is no longer Cain, nor goes out from the presence of God, nor dwells in the land of Nod, which is said to mean commotion. Against this evil of commotion the Psalmist prays, "Suffer not my feet to be moved;" and again, "Let not the hands of the wicked remove me;" and, "Those that trouble me will rejoice when I am moved:" and, "The Lord is at my right hand, that I should not be moved;" and so in innumerable places. This evil comes upon those who leave the presence of God, that is, His loving-kindness. Thus the Psalmist says, "I said in my prosperity, I shall never be moved." But observe what follows, "Lord, by Your favor You have given strength to my honor; You hid Your face, and I was troubled;" which teaches us that not in itself, but by participation in the light of God, can any soul possess beauty, or honor, or strength. The Manichæans should think of this, to keep them from the blasphemy of identifying themselves with the nature and substance of God. But they cannot think, because they are not content. The Sabbath of the heart they are strangers to. If they were content, as Cain was told to be, they would refer their sin to themselves; that is, they would lay the blame on themselves, and not on a race of darkness that no one ever heard of, and so by the grace of God they would prevail over their sin. But now the Manichæans, and all who oppose the truth by their various heresies, leave the presence of God, like Cain and the scattered Jews, and inhabit the land of commotion, that is, of carnal disquietude, instead of the enjoyment of God, that is instead of Eden, which is interpreted Feasting, where Paradise was planted. But not to depart too much from the argument of this treatise I must limit myself to a few, short remarks under this head.
Source: Reply to Faustus the Manichaean (New Advent)