Still long before the evil had reached this height, men felt the oppression of the priests and sighed for deliverance. The priests themselves had perceived, that if they did not apply a remedy, their usurped power would be lost, and, therefore, they invented the system of barter, so well known under the name of Indulgences. What they said was this:--"You penitents are not able to fulfil the tasks which are enjoined you? Well, then, we, priests of God, and your pastors, will take the heavy burden on ourselves. For a fast of seven weeks," says Regino, Abbot of Prum, "there will be paid by a rich man twentypence, by one less so tenpence, by the poor threepence, and so in like proportion for other things."[23] Bold voices were raised against this traffic, but in vain. [23] Libri Duo de Ecclesiasticis Disciplinis. The pope soon discovered the advantages which he might draw from these indulgences. In the thirteenth century, Alexander Hales, the irrefragable doctor, invented a doctrine well fitted to secure this vast resource to the Papacy, and a bull of Clement VII declared it an article of faith. Jesus Christ, it was said, did far more than was necessary to reconcile God to men; for that a single drop of his blood would have sufficed; but he shed much blood in order to found a treasury for his church, a treasury which even eternity should not be able to exhaust. The supererogatory merits of the saints, i. e. the value of the works which they did beyond their obligation, served also to augment this treasury, the custody and administration of which have been intrusted to Christ's vicar upon earth, who applies to each sinner for the faults committed after baptism these merits of Jesus Christ and the saints according to the measure and quantity which his sins render necessary. Who will venture to attack a practice whose origin is so holy? This inconceivable traffic soon extends, and becomes more complex. The philosophers of Alexandria speak of a fire in which souls are to be made pure. This philosophical opinion, which several ancient doctors had adopted, Rome declared to be a doctrine of the Church. The pope, by a bull, annexed purgatory to his domain. He decreed that man should there expiate what he might not be able to expiate here below, but that indulgences could deliver souls from that intermediate state in which their sins must otherwise detain them. This dogma is expounded by Thomas Aquinas in his famous theological Summa. Nothing was spared to fill the mind with terror. The torments which the purifying fire inflicts on those who become its victims were painted in dreadful colours. Even at the present day, in many Catholic countries, we see pictures exhibited in churches, or in the public streets, in which poor souls in the midst of burning flames are calling in agony for relief. Who could refuse the redemption money which, on falling into the treasury of Rome, was to ransom the soul from such sufferings?