Whether the power of the keys extends to the remission of guilt? [*St. Thomas here follows the opinion of Peter Lombard, and replies in the negative. Later in life he altered his opinion. Cf. TP, Question [62], Article [1]; TP, Question [64], Article [1]; TP, Question [86], Article [6]]

❌ Objection 1 : It would seem that the power of the keys extends to the remission of guilt. For it was said to the disciples (Jn. 20:23): "Whose sins you shall forgive, they are forgiven them." Now this was not said in reference to the declaration only, as the Master states (Sent. iv, D, 18), for in that case the priest of the New Testament would have no more power than the priest of the Old Testament. Therefore he exercises a power over the remission of the guilt.

❌ Objection 2 : Further, in Penance grace is given for the remission of sin. Now the priest is the dispenser of this sacrament by virtue of the keys. Therefore, since grace is opposed to sin, not on the part of the punishment, but on the part of the guilt, it seems that the priest operates unto the remission of sin by virtue of the keys.

❌ Objection 3 : Further, the priest receives more power by his consecration than the baptismal water by its sanctification. Now the baptismal water receives the power "to touch the body and cleanse the heart," as Augustine says (Tract. lxxx in Joan.). Much more, therefore, does the priest, in his consecration, receive the power to cleanse the heart from the stain of sin.