ANSWER:  The power to forgive sins. 

Jesus said to his Apostles:

"Peace be with you. As the Father has sent me, so I send you." And when he had said this, he breathed on them and said to them, "Receive the holy Spirit. Whose sins you forgive are forgiven them, and whose sins you retain are retained." (John 20:21-23)

St. John Chrysostom wrote: "Priests have received a power which God has given neither to angels nor to archangels. It was said to them: ‘Whatsoever you shall bind on earth shall be bound in heaven; and whatsoever you shall loose, shall be loosed.’ Temporal rulers have indeed the power of binding; but they can only bind the body. Priests, in contrast, can bind with a bond which pertains to the soul itself and transcends the very heavens. Did [God] not give them all the powers of heaven? ‘Whose sins you shall forgive,’ he says, ‘they are forgiven them; whose sins you shall retain, they are retained.’ What greater power is there than this? The Father has given all judgment to the Son. And now I see the Son placing all this power in the hands of men [Matt. 10:40; John 20:21–23]. They are raised to this dignity as if they were already gathered up to heaven" (The Priesthood 3:5 [ 387 A.D.]).


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