:
1 When the LORD thy God hath cut off the nations, whose land the LORD thy God giveth thee, and thou succeedest them, and dwellest in their cities, and in their houses; 2 Thou shalt separate three cities for thee in the midst of thy land, which the LORD thy God giveth thee to possess it. 3 Thou shalt prepare thee a way, and divide the coasts of thy land, which the LORD thy God giveth thee to inherit, into three parts, that every slayer may flee thither. 4 And this is the case of the slayer, which shall flee thither, that he may live: Whoso killeth his neighbour ignorantly, whom he hated not in time past; 5 As when a man goeth into the wood with his neighbour to hew wood, and his hand fetcheth a stroke with the axe to cut down the tree, and the head slippeth from the helve, and lighteth upon his neighbour, that he die; he shall flee unto one of those cities, and live: 6 Lest the avenger of the blood pursue the slayer, while his heart is hot, and overtake him, because the way is long, and slay him; whereas he was not worthy of death, inasmuch as he hated him not in time past. 7 Wherefore I command thee, saying, Thou shalt separate three cities for thee. 8 And if the LORD thy God enlarge thy coast, as he hath sworn unto thy fathers, and give thee all the land which he promised to give unto thy fathers; 9 If thou shalt keep all these commandments to do them, which I command thee this day, to love the LORD thy God, and to walk ever in his ways; then shalt thou add three cities more for thee, beside these three: 10 That innocent blood be not shed in thy land, which the LORD thy God giveth thee for an inheritance, and so blood be upon thee. 11 But if any man hate his neighbour, and lie in wait for him, and rise up against him, and smite him mortally that he die, and fleeth into one of these cities: 12 Then the elders of his city shall send and fetch him thence, and deliver him into the hand of the avenger of blood, that he may die. 13 Thine eye shall not pity him, but thou shalt put away the guilt of innocent blood from Israel, that it may go well with thee. 14 Thou shalt not remove thy neighbour's landmark, which they of old time have set in thine inheritance, which thou shalt inherit in the land that the LORD thy God giveth thee to possess it. 15 One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established. 16 If a false witness rise up against any man to testify against him that which is wrong; 17 Then both the men, between whom the controversy is, shall stand before the LORD, before the priests and the judges, which shall be in those days; 18 And the judges shall make diligent inquisition: and, behold, if the witness be a false witness, and hath testified falsely against his brother; 19 Then shall ye do unto him, as he had thought to have done unto his brother: so shalt thou put the evil away from among you. 20 And those which remain shall hear, and fear, and shall henceforth commit no more any such evil among you. 21 And thine eye shall not pity; but life shall go for life, eye for eye, tooth for tooth, hand for hand, foot for foot.
[AD 420] Jerome on Deuteronomy 19:5
The very words of Scripture indicate that even ignorance is a sin. This is why Job offers holocausts for his sons, lest perchance they may have sinned unwittingly in thought. And if a man is killed by the iron of an axe that flies off the handle when a man is hewing wood, the wood hewer is ordered to flee to a city of refuge and remain in that place until the death of the high priest. That is to say, [he remains there] until he is redeemed by the blood of the Savior, either in the house of baptism or by repentance, which supplies the efficacy of the grace of baptism through the ineffable mercy of the Savior. [The Savior] does not wish anybody to perish, nor does he find his delight in the death of sinners, but [he would] rather that they be converted from their way and live.

[AD 604] Gregory the Dialogist on Deuteronomy 19:5
Now we go into a wood with a friend as often as we turn our attention to the sins of subjects, and guilelessly we hew wood when we cut away the faults of sinners with loving intention. But the axe flies from the hand when reproof oversteps itself and degenerates into hardship. The iron flies from the handle when the words of reproof are excessively harsh and the friend is struck and killed. Thus a contumelious utterance kills the spirit of love in the hearer.

[AD 397] Ambrose of Milan on Deuteronomy 19:14
And since we have taken an example drawn from agriculture, enjoin them to keep the laws about borders intact and to guard the ancestral boundaries which the law protects. The good will of a neighbor is often more important than the love of a brother. For a brother is often far away, but a neighbor, close at hand, is a witness to the whole of one’s life and a judge of one’s dealings.

[AD 397] Ambrose of Milan on Deuteronomy 19:14
But on the contrary, if your eye has looked upon a woman to covet her, you have opened a wound, you have driven a weapon into your body. Your very members become tools of sin. If you look upon the property of orphans and drive them from the dwellings of their fathers, you are changing the landmarks that your forefathers set. Your members are tools of iniquity. And so the passions are the author of guilt and not the flesh, for the flesh is the servant of the will.

[AD 56] 2 Corinthians on Deuteronomy 19:15
This is the third time I am coming to you. In the mouth of two or three witnesses shall every word be established. [Deuteronomy 19:15] I told you before, and foretell you, as if I were present, the second time; and being absent now I write to them which heretofore have sinned, and to all other, that, if I come again, I will not spare
[AD 60] Matthew on Deuteronomy 19:15
Moreover if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother. But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established. [Deuteronomy 19:15] And if he shall neglect to hear them, tell it unto the church: but if he neglect to hear the church, let him be unto thee as an heathen man and a publican.
[AD 386] Cyril of Jerusalem on Deuteronomy 19:15
[Christ] did then truly rise, and after he had risen, he was seen again by his disciples. And the twelve disciples were witnesses of his resurrection, testifying not with words meant to please but contending for the truth of the resurrection even unto torture and death. Further, “on the word of two or three witnesses every word may be confirmed,” according to Scripture. There are twelve witnesses to the resurrection of Christ, and do you still disbelieve in the resurrection?

[AD 430] Augustine of Hippo on Deuteronomy 19:15
Therefore if a people composed of a great multitude was found a false witness, how must it be understood, “In the mouth of two or three witnesses every word shall stand,” except that in this way. The Trinity, in which is unending stability of truth, was revealed through a mystery. Do you want to have a good case? Have two or three witnesses, the Father and the Son and the Holy Spirit.

[AD 430] Augustine of Hippo on Deuteronomy 19:15
As a matter of fact, a single witness generally speaks the truth, while a mob may tell lies. And the world, in its conversion to Christianity, believed one apostle preaching the gospel rather than the mistaken multitude who persecuted him.

[AD 465] Maximus of Turin on Deuteronomy 19:15
At the birth of the Savior, then, there was fulfilled that divine sentence which says, “Every word shall stand with two or three witnesses.” For see, the Word of God is born with the Trinity as witness. For indeed, in the womb of holy Mary—when the Holy Spirit comes upon her, when the Most High overshadows her, when Christ is begotten—there is implied a confession of faith in him.