Pseudo-Cyprian

The cardinal principles of chastity, brothers, are ancient. How so? Because they were ordained at the same time as the human race itself. For both her own husband belongs to the woman, for the reason that she may know no other besides him, and because the woman is given to the man. This latter is in order that, when what is his own has been given to him, he should seek nothing belonging to another.… Christ gave this judgment when, having been questioned, he said that a wife must not be put away except because of adultery. Thus did he honor chastity. From this has come the levitical decree, “You shall not allow adulteresses to live.” Therefore, the apostle says, “This is the will of God, your sanctification, that you abstain from fornication.”

Moreover, in the same [Gospel] he also says, “All who have come before are thieves and robbers.” Who are such but the deserters of the faith and the transgressors of God’s church, who strive against God’s ordinance—whom the Holy Spirit rightly rebukes by the prophet, saying, “You have taken counsel, but not by me; and have made a confederacy, but not by my Spirit, to add sin to sin.”