Thomas Aquinas

“ But an offense against God is infinite, since it is measured by the person against whom it is committed, for it is a greater offense to strike a prince than anyone else. Therefore, as no action of man can be infinite, it seems that he cannot make satisfaction to God.
Objection 2: Further, a slave cannot make compensation for a debt, since all that he has is his master's. But we are the slaves of God, and whatever good we have, we owe to Him. Therefore, as satisfaction is compensation for a past offense, it seems that we cannot offer it to God. ”

“ Wherefore just as one man is not disposed thereto by another's act, so one man does not merit the essential reward for another, unless his merit has infinite efficacy, as the merit of Christ, whereby children come to eternal life through Baptism. On the other hand, the temporal punishment due to sin after the guilt has been forgiven is not measured according to the disposition of the man to whom it is due, since sometimes the better man owes a greater debt of punishment. ”

“ Nor is it necessary that the one for whom satisfaction is made should be unable to make satisfaction himself, for even if he were able, he would be released from his debt when the other satisfied in his stead. But this is necessary in so far as the satisfactory punishment is medicinal: so that a man is not to be allowed to do penance for another, unless there be evidence of some defect in the penitent, either bodily, so that he is unable to bear it, or spiritual, so that he is not ready to undergo it. ”

“ This argument proves that it is impossible to make equivalent satisfaction to God, but not that it is impossible to make sufficient satisfaction to Him. For though man owes God all that he is able to give Him, yet it is not necessary for his salvation that he should actually do the whole of what he is able to do, for it is impossible for him, according to his present state of life, to put forth his whole power into any one single thing, since he has to be heedful about many things. ”

“ If this man bound himself to undergo a certain punishment, he would not be released from the debt before paying it: wherefore he himself will suffer the punishment, as long as the other makes satisfaction for him: and if he do not this, then both are debtors in respect of fulfilling this punishment, one for the sin committed, the other for his omission, so that it does not follow that one sin is twice punished. ”

“ Though original sin has less of the nature of sin than actual sin has, yet it is a more grievous evil, because it is an infection of human nature itself, so that, unlike actual sin, it could not be expiated by the satisfaction of a mere man.
Art. 2 - Whether one man can fulfill satisfactory punishment for another? Objection 1: It would seem that one man cannot fulfill satisfactory punishment for another. Because merit is requisite for satisfaction. ”

“ Therefore it seems that one can bear the burden of punishment laid upon another.
Further, charity avails more before God than before man. Now before man, one can pay another's debt for love of him. Much more, therefore, can this be done before the judgment seat of God. ”

“ Now one man cannot merit or demerit for another, since it is written (Ps. 61:12) : "Thou wilt render to every man according to his works." Therefore one man cannot make satisfaction for another.
Objection 2: Further, satisfaction is condivided with contrition and confession. But one man cannot be contrite or confess for another. Neither therefore can one make satisfaction for another. ”

“ Now in giving honor to one's parents or to the gods, as indeed the Philosopher says (Ethic. viii, 14) , it is impossible to repay them measure for measure, but it suffices that man repay as much as he can, for friendship does not demand measure for measure, but what is possible. ”