II. The woman who purposely destroys her unborn child is guilty of murder. With us there is no nice enquiry as to its being formed or unformed. In this case it is not only the being about to be born who is vindicated, but the woman in her attack upon herself; because in most cases women who make such attempts die. The destruction of the embryo is an additional crime, a second murder, at all events if we regard it as done with intent. The punishment, however, of these women should not be for life, but for the term of ten years. And let their treatment depend not on mere lapse of time, but on the character of their repentance.
...
VII. Abusers of themselves with mankind, and with beasts, as also murderers, wizards, adulterers, and idolaters, are deserving of the same punishment. Whatever rule you have in the case of the rest, observe also in their case. There can, however, be no doubt that we ought to receive those who have repented of impurity committed in ignorance for thirty years. In this case there is ground for forgiveness in ignorance, in the spontaneity of confession, and the long extent of time. Perhaps they have been delivered to Satan for a whole age of man that they may learn not to behave unseemly; wherefore order them to be received without delay, specially if they shed tears to move your mercy, and show a manner of living worthy of compassion.
VIII. The man who in a rage has taken up a hatchet against his own wife is a murderer. But it is what I should have expected from your intelligence that you should very properly remind me to speak on these points more fully, because a wide distinction must be drawn between cases where there is and where there is not intent. A case of an act purely unintentional, and widely removed from the purpose of the agent, is that of a man who throws a stone at a dog or a tree, and hits a man. The object was to drive off the beast or to shake down the fruit. The chance comer falls fortuitously in the way of the blow, and the act is unintentional. Unintentional too is the act of any one who strikes another with a strap or a flexible stick, for the purpose of chastising him, and the man who is being beaten dies. In this case it must be taken into consideration that the object was not to kill, but to improve, the offender. Further, among unintentional acts must be reckoned the case of a man in a fight who when warding off an enemy's attack with cudgel or hand, hits him without mercy in some vital part, so as to injure him, though not quite to kill him. This, however, comes very near to the intentional; for the man who employs such a weapon in self defence, or who strikes without mercy, evidently does not spare his opponent, because he is mastered by passion. In like manner the case of any one who uses a heavy cudgel, or a stone too big for a man to stand, is reckoned among the unintentional, because he does not do what he meant: in his rage he deals such a blow as to kill his victim, yet all he had in his mind was to give him a thrashing, not to do him to death. If, however, a man uses a sword, or anything of the kind, he has no excuse: certainly none if he throws his hatchet. For he does not strike with the hand, so that the force of the blow may be within his own control, but throws, so that from the weight and edge of the iron, and the force of the throw, the wound cannot fail to be fatal.
On the other hand acts done in the attacks of war or robbery are distinctly intentional, and admit of no doubt. Robbers kill for greed, and to avoid conviction. Soldiers who inflict death in war do so with the obvious purpose not of fighting, nor chastising, but of killing their opponents. And if any one has concocted some magic philtre for some other reason, and then causes death, I count this as intentional. Women frequently endeavour to draw men to love them by incantations and magic knots, and give them drugs which dull their intelligence. Such women, when they cause death, though the result of their action may not be what they intended, are nevertheless, on account of their proceedings being magical and prohibited, to be reckoned among intentional homicides. Women also who administer drugs to cause abortion, as well as those who take poisons to destroy unborn children, are murderesses. So much on this subject.
...
XI. The man who is guilty of unintentional homicide has given sufficient satisfaction in eleven years. We shall, without doubt, observe what is laid down by Moses in the case of wounded men, and shall not hold a murder to have been committed in the case of a man who lies down after he has been struck, and walks again leaning on his staff. Exodus 21:19 If, however, he does not rise again after he has been struck, nevertheless, from there being no intent to kill, the striker is a homicide, but an unintentional homicide.
...
XIII. Homicide in war is not reckoned by our Fathers as homicide; I presume from their wish to make concession to men fighting on behalf of chastity and true religion. Perhaps, however, it is well to counsel that those whose hands are not clean only abstain from communion for three years.
(Emphasis added)