He has done his neighbour an injury which in a certain sense is irreparable. He should make what reparation he can. In this and similar cases it is a disputed point among theologians whether the adulterer is obliged to offer a money compensation for the injury. If he is convicted and sentenced to pay damages by lawful authority, he will certainly be bound to do so in conscience. But apart from such a sentence, he cannot be obliged to compensate the injured husband in money, because there is no common measure between such injuries and compensation in goods of another order.
Commutative justice looks at objective equality, and prescribes that it be preserved.
For this reason Aristotle called this species of justice corrective, inasmuch as it corrects and remedies the inequality which an act of injustice produces between the injurer and the party injured. The one has less than he ought to have, because the other has taken it away, and they will not be quits until restitution is made. In cases where an injury is irreparable, the injurer will be bound to do what he can so that the injured party may be content. This is called making satisfcation, to distinguish it from making restitution in the strict sense. A violation of commutative justice alone imposes the obligation of making restitution, for when charity or obedience or any of the other virtues is violated, there is indeed a consequent obligation of repenting for the sin, but there is no obligation of performing the omitted act of charity or obedience now.