What hast thou done? The voice of thy brother's blood Moses shows that Cain gained nothing by his tergiversation. God first inquired where his brother was; he now more closely urges him, in order to extort an unwilling confession of his guilt; for in no racks or tortures of any kind is there so much force to constrain evildoers, as there was efficacy in the thunder of the Divine voice to cast down Cain in confusion to the ground. For God no longer asks whether he had done it; but, pronouncing in a single word that he was the doer of it, he aggravates the atrocity of the crime. We learn, then, in the person of one man, what an unhappy issue of their cause awaits those, who desire to extricate themselves by contending against God. For He, the Searcher of hearts, has no need of a long, circuitous course of investigation; but, with one word, so fulminates against those whom he accuses, as to be sufficient, and more than sufficient, for their condemnation. Advocates place the first kind of defense in the denial of the fact; where the fact cannot be denied, they have recourse to the qualifying circumstances of the case. Cain is driven from both these defenses; for God both pronounces him guilty of the slaughter, and, at the same time, declares the heinousness of the crime. And we are warned by his example, that pretexts and subterfuges are heaped together in vain, when sinners are cited to the tribunal of God. The voice of thy brother's blood crieth. God first shows that he is cognizant of the deeds of men, though no one should complain of or accuse them; secondly that he holds the life of man too dear, to allow innocent blood to be shed with impunity; thirdly, that he cares for the pious not only while they live, but even after death. However earthly judges may sleep, unless an accuser appeals to them; yet even when he who is injured is silent the injuries themselves are alone sufficient to arouse God to inflict punishment. This is a wonderfully sweet consolation to good men, who are unjustly harassed, when they hear that their own sufferings, which they silently endure, go into the presence of God of their own accord, to demand vengeance. Abel was speechless when his throat was being cut, or in whatever other manner he was losing his life; but after death the voice of his blood was more vehement than any eloquence of the orator. Thus oppression and silence do not hinder God from judging, or the cause which the world supposes to be buried. This consolation affords us most abundant reason for patience when we learn that we shall lose nothing of our right, if we bear injuries with moderation and equanimity; and that God will be so much the more ready to vindicate us, the more modestly we submit ourselves to endure all things; because the placid silence of the soul raises effectual cries, which fill heaven and earth. Nor does this doctrine apply merely to the state of the present life, to teach us that among the innumerable dangers by which we are surrounded, we shall be safe under the guardianship of God; but it elevates us by the hope of a better life; because we must conclude that those for whom God cares shall survive after death. And, on the other hand, this consideration should strike terror into the wicked and violent, that God declares, that he undertakes the causes deserted by human patronage, not in consequence of any foreign impulse, but from his own nature; and that he will be the sure avenger of crimes, although the injured make no complaint. Murderers indeed often exult, as if they had evaded punishment; but at length God will show that innocent blood has not been mute, and that he has not said in vain, the death of the saints is precious in his eyes,' (Psalm 115:17.) Therefore, as this doctrine brings relief to the faithful, lest they should be too anxious concerning their life, over which they learn that God continually watches; so does it vehemently thunder against the ungodly who do not scruple wickedly to injure and to destroy those whom God has undertaken to preserve.

What hast thou done? - The Lord now charges him with his guilt: "The voice of thy brother's blood crieth unto me from the soil." In the providence of God blood has a voice crying to him to which he cannot but give heed. It is vain, then, to attempt concealment.

The voice of thy brother's blood - It is probable that Cain, having killed his brother, dug a hole and buried him in the earth, hoping thereby to prevent the murder from being known; and that this is what is designed in the words, Thy brother's blood crieth unto me From The Ground - which hath opened her mouth to receive it from thy hand. Some think that by the voice of thy brother's blood the cries of Abel's widow and children are to be understood, as it is very probable that he was father of a family; indeed his occupation and sacrifices seem to render this probable, and probability is all we can expect on such a subject. God represents these as calling aloud for the punishment of the murderer; and it is evident that Cain expected to fall by the hands of some person who, from his consanguinity, had the right of the avenger of blood; for now that the murder is found out, he expects to suffer death for it. See Genesis 4:14.

And he said, What hast thou done? the (i) voice of thy brother's blood crieth unto me from the ground.
(i) God avenges the wrongs against his saints, though no one complains: for the iniquity itself cries for vengeance.

And he said,.... Not Cain, the last speaker, but the Lord God:
what hast thou done? what an heinous crime hast thou committed! how aggravated is it! I know what thou hast done; thou hast slain thy brother, thine own, thine only brother, a holy, righteous, and good man, who never gave thee any offence, or any just occasion of shedding his innocent blood: this he said as knowing what he had done, and to impress his mind with a sense of the evil, and to bring him to a confession of it, before the sentence was passed, that it might appear to all to be just, and of which there was full proof and evidence, as follows:
the voice of thy brother's blood crieth unto me from the ground; where it was split, and in which it was covered and hid, and where perhaps Cain had buried his body, that it might not be seen, and the murder not discovered; but God saw what was done, and the voice of innocent blood came into his ears, and cried for vengeance at his hands: it is in the original, "the voice of thy brother's bloods" (s), in the plural; which the Jews generally understood of the posterity that would have descended from Abel, had he not been murdered: the Targum of Onkelos is,"the voice of the blood of the seeds or generations that should come from thy brother;''see 2-Kings 9:26 or it may respect the blood of the seed of the woman, of all the righteous ones that should be slain in like manner. The Jerusalem Targum is,"the voice of the bloods of the multitude of the righteous that shall spring from Abel thy brother,''or succeed him; see Matthew 23:35. Jarchi thinks it has reference to the many wounds which Cain gave him, from whence blood sprung; and every wound and every drop of blood, as it were, cried for vengeance on the murderer.
(s) "vox Sanguinum", Pagninus, Montanus, &c.

the voice of thy brother's blood crieth unto me--Cain, to lull suspicion, had probably been engaging in the solemnities of religion when he was challenged directly from the Shekinah itself.

And he said, What hast thou done? - Thou thinkest to conceal it, but the evidence against thee is clear and uncontestable, the voice of thy brother's blood crieth - He speaks as if the blood itself were both witness and prosecutor, because God's own knowledge testified against him, and God's own justice demanded satisfaction. The blood is said to cry from the ground, the earth, which is said, Genesis 4:11, to open her mouth to receive his brother's blood from his hand. The earth did as it were blush to see her own face stained with such blood; and therefore opened her mouth to hide that which she could not hinder.