150 AD Didache
"The second commandment of the teaching: You shall not murder. You shall not commit adultery. You shall not seduce boys. You shall not commit fornication. You shall not steal. You shall not practice magic. You shall not use potions. You shall not procure [an] abortion, nor destroy a newborn child" (Didache 2:1)
250 AD Diognetus
(a likely reference to both exposure of infants to die and abortion): "(Christians) marry, like everyone else, and they beget children, but they do not cast out their offspring." (Letter of Diognetus (late 2nd or 3rd century; ch.5, vs.6)
314 AD Council of Ancyra
"Concerning women who commit fornication, and destroy that which they have conceived, or who are employed in making drugs for abortion, a former decree excluded them until the hour of death, and to this some have assented. Nevertheless, being desirous to use somewhat greater lenity, we have ordained that they fulfill ten years [of penance], according to the prescribed degrees" (canon 21).
374 AD Basil the Great
"He that kills another with a sword, or hurls an axe at his own wife and kills her, is guilty of willful murder; not he who throws a stone at a dog, and unintentionally kills a man, or who corrects one with a rod, or scourge, in order to reform him, or who kills a man in his own defense, when he only designed to hurt him. But the man, or woman, is a murderer that gives a philtrum, if the man that takes it die upon it; so are they who take medicines to procure abortion; and so are they who kill on the highway, and rapparees" ((First Canonical Letter, canon 8).
374 AD Basil the Great
"Let her that procures abortion undergo ten years' penance, whether the embryo were perfectly formed, or not" (First Canonical Letter, canon 2).
391 AD John Chrysostom
"Wherefore I beseech you, flee fornication . . . Why sow where the ground makes it its care to destroy the fruit?--where there are many efforts at abortion?--where there is murder before the birth? For even the harlot you do not let continue a mere harlot, but make her a murderess also. You see how drunkenness leads to prostitution, prostitution to adultery, adultery to murder; or rather to a something even worse than murder. For I have no name to give it, since it does not take off the thing born, but prevents its being born. Why then do thou abuse the gift of God, and fight with His laws, and follow after what is a curse as if a blessing, and make the chamber of procreation a chamber for murder, and arm the woman that was given for childbearing unto slaughter? For with a view to drawing more money by being agreeable and an object of longing to her lovers, even this she is not backward to do, so heaping upon thy head a great pile of fire. For even if the daring deed be hers, yet the causing of it is thine" (Homilies on Romans 24).
400 AD The Apostolic Constitutions
"Thou shalt not use magic. Thou shalt not use witchcraft; for He says, 'You shall not suffer a witch to live' [Ex. 22:18]. Thou shall not slay thy child by causing abortion, nor kill that which is begotten; for "everything that is shaped, and has received a soul from God, if it be slain, shall be avenged, as being unjustly destroyed." (Apostolic Constitutions 7:3).