From the Council of Hertford, in England, under Theodore, Bishop of Canterbury, A.D. 673

Canon X. On Marriages. That it be lawful for no one to have anything except legitimate marriage. Let no one commit incest. Let no one leave his own spouse except as the holy Gospel teaches, for the cause of fornication. But if anyone has cast out his own legitimate spouse joined to him by matrimony, if he rightly wishes to be a Christian, let him be coupled to no other, but let him remain thus or be reconciled to his own wife.

Here you have the Catholic dogma expressly proposed: indeed the dismissal of the wife is permitted in the case of fornication, yet in such a way that he does not accept another. From this you understand how badly, among the capitula ascribed to the same Theodore, this also is reckoned, CXVI: "Whose wife commits fornication, it is lawful to dismiss her and accept another; and it is not lawful for a woman to commit fornication and accept another for money."