82. The sacrament of penance is, with the Mass, of especial historical importance. When a bishop ordained a priest, he said to him: "Receive ye the Holy Ghost: whose soever sins ye forgive, they are forgiven them: whose soever sins ye retain, they are retained." In this way the priest was intrusted with the keys of the kingdom of heaven. There was no hope of salvation for one who had fallen into mortal sin unless he received--or at least desired and sought--the absolution of the priest. To one who scorned the priest's ministrations the most sincere and prayerful repentance could not by itself bring forgiveness in the eyes of the Church. Before the priest could utter the solemn "I absolve thee from thy sins," the sinner must have duly confessed his sins and have expressed his vehement detestation of them and his firm resolve never more to offend. It is clear that the priest could not pronounce judgment unless he had been told the nature of the case. Nor would he be justified in absolving an offender who was not truly sorry for what he had done. Confession and penitence were, therefore, necessary preliminaries to absolution.[143] [Sidenote: Penance and purgatory.] Absolution did not free the contrite sinner from all the results of his sin. It cleared the soul of the deadly guilt which would otherwise have been punished by everlasting suffering, but did not exempt the penitent from temporal penalties. These might be imposed by the priest in this world or suffered after death in the fires of purgatory, which cleansed the soul and prepared it for heaven. [Sidenote: Nature of penance.] The punishment prescribed by the priest was called _penance_. This took a great variety of forms. It might consist in fasting, repeating prayers, visiting holy places, or abstaining from one's ordinary amusements. A journey to the Holy Land was regarded as taking the place of all penance. Instead, however, of requiring the penitent actually to perform the fasts, pilgrimages, or other sacrifices imposed as penance by the priest, the Church early permitted him to change his penance into a contribution, to be applied to some pious enterprise, like building a church or bridge, or caring for the poor and sick. [Sidenote: The Mass.] [Sidenote: Transubstantiation.]