The practice of granting Indulgences was universally prevalent and was universally accepted; but it was not easy to give an explanation of the system, in the sense of showing that it was an essential element in Christian discipline. No mediæval theologian attempted to do any such thing. Bonaventura and Thomas Aquinas, the two great Schoolmen who did more than any others to provide a theological basis for the system, tell us quite frankly that it is their business to accept the fact that Indulgences do exist as part of the penitentiary discipline of the Church, and, accepting it, they thought themselves bound to construct a reasonable theory.(160) The practice altered, and new theories were needed to explain the variations. It is needless to say that these explanations did not always agree; and that there were very great differences of opinion about what an Indulgence really effected for the man who bought it. Of all these disputed questions the most important was: Did an Indulgence give remission for the guilt of sin, or only for certain penalties which followed the sinful deed? This is a question about which modern Romanists are extremely sensitive. The universal answer given by all defenders of Indulgences who have written on the subject since the Council of Trent, is that guilt (_culpa_) and eternal punishment (_pœnæ eternæ_) are dealt with in the Sacrament of Penance, and that Indulgences relate only to temporal punishments, including under that designation the pains of Purgatory. This modern opinion is confirmed by the most eminent authorities of the mediæval Church. It has been accepted in the description of the theory of Indulgences given above, since it has been said that the principal use of Indulgences was to secure against Purgatory. But these statements do not exhaust the question. Mediæval theology did not create Indulgences, it only followed and tried to justify the practices of the Pope and of the Roman Curia,—a rather difficult task. The question still remains whether some of the Papal Bulls promulgating Indulgences did not promise the removal of guilt as well as security against temporal punishments. If these be examined, spurious Bulls being set aside, it will be found that many of them make no mention of the need of previous confession and of priestly absolution; that one or two expressly make mention of a remission of guilt as well as of penalty; and that many (especially those which proclaim a Jubilee Indulgence) use language which inevitably led intelligent laymen like Dante to believe that the Popes did proclaim the remission of guilt as well as of penalty. Of course, it may be said that in those days the distinction between guilt (_culpa_) and penalty (_pœna_) had not been very exactly defined, and that the phrase _remission of sins_ was used to denote both remission of guilt and remission of penalty; still it is difficult to withstand the conclusion that, even in theory,