By Carol Symes, University of Illinois Urbana-Champaign
The institutionalization of purgatory as a doctrine of the Roman Church crystalized in the 12th century with growing claims to papal power. In the 1160s, Pope Alexander III mandated that only the papal court had the right to canonize saints, which meant that anyone not officially recognized by the Church as such was de facto headed for purgatory.

The Theology of Purgatory
In 1215, at the Fourth Lateran Council of the Church, Pope Innocent III took charge of the other end of the judgment process by declaring that only an ordained priest could assign penance or offer absolution from sin, thereby making the priesthood the arbiters of who was, or was not, making progress on the path to salvation. Thereafter, the theology of purgatory was codified by Thomas Aquinas and other scholastic theologians; in 1245, at the First Council of Lyon, it was officially adopted as a dogma of the Church—that is, ‘a truth necessary for salvation’.
As Purgatory became ever more firmly fixed in the teachings of the Roman Church, the Church found that it needed to alleviate the stresses and worries that this dogma now occasioned. How was an individual to know when a loved one’s soul had been liberated from purgatory? Just how many penitential acts or masses were needed? Could one quantify the amount of penance or prayer needed to alleviate purgatorial sufferings?
Around 1230, the idea that a living person could win a soul’s remission of sins for a specific number of days or years was buttressed by the concept of a heavenly treasury of merits—that is, the aggregation of all the holy deeds done by Christ and his saints over time, which existed in a spiritual bank vault and could be drawn upon to help save souls.
The ‘Indulgences’
This idea, in turn, became the theological basis for the granting or purchase of indulgences, from the Latin verb meaning ‘to be lenient, to make allowance for’. In addition to performing acts of penance on one’s own behalf, or offering prayers and masses for the dead (which cost money), the Church was increasingly allowing bishops and other officials to collect money from the sale of indulgence certificates. This money was ostensibly being exchanged for a withdrawal of grace from the treasury of merits. In return for this indulgence, the Church official could then use the money to fund any number of projects: hospitals, roads, schools, churches.
Of course, many medieval Christians suspected, rightly, that the sale of indulgences was putting money directly into the clergy’s pockets.
Although some popes and theologians accordingly warned against the abuse of indulgences, especially when extracted from the gullible on frivolous grounds, their sale had become an essential financial pillar of local churches by the 14th century, and open to more and more abuse. Critics such as the English bureaucrat and poet, Geoffrey Chaucer, denounced the rapacious ‘pardoners’ who peddled indulgences by promising worldly happiness as well as eternal salvation and other benefits.
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Martin Luther’s Ninety-five Theses
In real life, indulgence certificates were often mere forgeries and—depending on one’s perspective—arguably worthless even if genuine. And after the invention of printing in the 1450s, they could be mass produced. An indulgence from London, dated to 1497, has been made out in favor of its purchaser, with the sign manual (or initials) of the pardoner on the right. Another, printed in Johannes Gutenberg’s own city of Mainz, is blank and ready for sale.
It was precisely this flagrant flogging of indulgences that became the proximate cause of Martin Luther’s scathing Ninety-five Theses, many of which deal with the Church’s tacit or explicit condoning of exploitative practices. The immediate catalyst was the aggressive sale of indulgences to finance the wholesale reconstruction of St. Peter’s Basilica in Rome—the present-day Vatican.

In northern Germany, where Luther taught at the University of Wittenberg, a friar called Johann Tetzel became famous for the catchphrase, “As soon as coin in the coffer rings, a soul from Purgatory springs”, which Luther quotes with disgust in Thesis 28.
Justification by Faith
In Thesis 37, Luther declared, “Any Christian whatsoever, who is truly repentant, enjoys full remission from sin, and this is given to him without letters of indulgence.” This statement would later be elaborated in Luther’s 1520 treatise, On the Freedom of a Christian, in which he returned to Saint Augustine to develop his key doctrine—‘justification by faith’.
For Luther, justification by faith meant that there was no need for atonement through purgatory. As Saint Augustine, the bishop of Hippo Regis had concluded, “the faith which works through love” (quoting Saint Paul in I Corinthians) is all that is crucial to salvation, and that sacraments could not save even baptized infants from sinning unwittingly. Luther reasoned that ‘the faith which works through love’ means that anyone who has that faith will do good works, and that sacraments are not necessary for salvation: the exact opposite of the Roman Church’s teaching.
For Luther, works, whether good deeds or sacraments, as he says, “being inanimate things, cannot glorify God, although they can, if faith is present, be done to the glory of God”.
The Anticlerical Sentiment
In the final salvos of his 95 debating points, Luther declares, passionately, in theses 81 and 82:
The immoderate preaching of indulgences makes it difficult for learned men to guard the pope against false accusations, or at least from the keen criticisms of the laity. They ask: “Why does not the pope liberate everyone from Purgatory (a most holy thing), because of the extreme necessity of their souls?” This would morally be the best of all reasons. Yet he redeems souls only for money.
This accusation against the pope and his greed was at the heart of most anticlerical sentiment in late-medieval Europe, even before the Reformation, and it continued long after it.
In the later 16th century, a miller called Domenico Scandella, nicknamed Menocchio, would find himself on trial before the Inquisition in northern Italy. Among his baldly stated heresies is the opinion that the post-Reformation Roman Catholic Church is “nothing but a business” because priests charge money for performing the sacraments, as well as for indulgences.
Common Questions about the Roman Church and the Institutionalization of Purgatory
The theology of Purgatory was codified by Thomas Aquinas and other scholastic theologians.
Many medieval Christians suspected, rightly, that the sale of indulgences was putting money directly into the clergy’s pockets.
For Martin Luther, justification by faith meant that there was no need for atonement through purgatory.