A reflection on our age of carbon indulgences

By Timothy Page

When Johann Tetzel proclaimed “As soon as the coin in the coffer rings, the soul from purgatory springs” in the 16th century, he expressed the culmination of centuries of theological development that would later find an unexpected echo in modern carbon credits and environmental economics.

The theological foundation for indulgences rested on several interconnected doctrines developed over centuries. The Church taught that while sacramental confession absolved the guilt of sin, temporal punishment remained due. This debt could be paid either through penance in this life or suffering in purgatory.

The concept of purgatory itself, formally defined at the Council of Florence in 1439, provided the theological space for indulgences to operate (Le Goff, 1984).

The Church’s power to grant indulgences stemmed from the doctrine of the “treasury of merit” (thesaurus meritorum), first formally articulated by Hugh of St. Cher in 1230. This treasury contained the infinite merits of Christ, combined with the surplus good works of the Virgin Mary and the saints.

Thomas Aquinas provided crucial theological justification in his “Summa Theologica” (1265-1274), arguing that the Church could transfer merit from this spiritual treasury to individual sinners through its power of the keys given by Christ to Peter. This created a theoretical framework for a spiritual economy of salvation, where merit could be transferred from one party to another under Church authority.

By the late 15th century, this system evolved into a sophisticated financial mechanism. Pope Sixtus IV’s 1476 declaration that indulgences could help souls already in purgatory effectively created a futures market in salvation (Shaffern, 2006).

The monetization of absolution reached its peak under Pope Leo X, who used indulgence revenues to fund St. Peter’s Basilica construction. The practice of offering different levels of indulgence for different payments created a price structure for salvation remarkably similar to today’s tiered carbon offset markets.

Today’s carbon credit market operates on strikingly similar principles, though in a secular context. Just as the medieval Church created a system to quantify and trade spiritual merit, modern environmental policies have created a marketplace for trading environmental impact. 

Companies exceeding emission limits can purchase credits from those polluting less, creating what economists call a “right to pollute” market. Like medieval pardoners, modern carbon credit brokers serve as intermediaries, profiting from the exchange of these ethical offsets.

The parallel failures of both systems stem from their similar theoretical weaknesses. Medieval theologians like Cardinal Cajetan warned that indulgences were being misunderstood as permission to sin rather than aid to genuine repentance (O’Malley, 2013). Similarly, modern critics argue that carbon credits become permission to pollute rather than incentives for genuine environmental reform.

In both systems, money changed hands but no net reduction in transgression occurred – medieval sin continued unabated, just as modern carbon trading results in no net reduction in global emissions.

Where medieval pardoners falsified papal bulls and inflated spiritual claims, modern studies show up to 94% of rainforest carbon offsets are “phantom credits” (West et al., 2023). Medieval pardoners became wealthy through commission-based sales, just as contemporary carbon credit brokers extract billions from market transactions.

The institutional resistance to reform mirrors itself across centuries. When Cardinal Albert of Brandenburg authorized new indulgences to pay off debts in 1517, he exemplified the system’s corruption, just as carbon markets continue despite mounting evidence of their ineffectiveness.

Professor Kevin Anderson of the Tyndall Centre emphasizes: “Carbon offsetting is worse than doing nothing. It is without scientific legitimacy, is dangerously misleading, and almost certainly contributes to a net increase in the absolute rate of global emissions growth” (Anderson, 2012).

The fundamental flaw in both systems lies in their attempt to monetize moral obligation without addressing root causes. Just as paying for indulgences didn’t reduce sinful behavior, purchasing carbon credits doesn’t reduce total emissions. Instead, both systems create an illusion of absolution while enabling continued harmful practices.

Environmental philosopher Michael Sandel draws this direct comparison: “The carbon trade, like the indulgence trade, encourages a kind of medieval reasoning that distracts us from the real work of finding solutions” (Sandel, 2012).

This “medieval reasoning” has real-world consequences. While the global carbon credit market reached $851 billion in 2021 (Refinitiv, 2022), global emissions continued to rise.

The transformation of ethical obligations into tradable commodities represents a fundamental misunderstanding of both spiritual and environmental responsibility. In both cases, the creation of a market for absolution serves primarily to ease the conscience of the wealthy while doing little to address the underlying problems.

The medieval church at least had the excuse of dealing with unprovable spiritual claims; modern carbon markets attempt to quantify environmental impact but often fail to deliver verifiable results.

Sources:

Anderson, K. (2012). “The Inconvenient Truth of Carbon Offsets.” Nature Climate Change, 2(6), 307-309.

Le Goff, J. (1984). The Birth of Purgatory. University of Chicago Press.

MacCulloch, D. (2003). The Reformation: A History. Viking Press.

O’Malley, J. W. (2013). Trent: What Happened at the Council. Harvard University Press.

Refinitiv. (2022). “Carbon Market Year in Review 2021.” Thomson Reuters.

Sandel, M. (2012). What Money Can’t Buy: The Moral Limits of Markets. Farrar, Straus and Giroux.

Shaffern, R. (2006). The Medieval Theology of Indulgences. Cambridge University Press.

Southern, R.W. (1990). The Church in Medieval Theology. Cambridge Medieval Textbooks.

Swanson, R.N. (2007). Indulgences in Late Medieval England: Passports to Paradise? Cambridge University Press.

UNFCCC. (2008). “Kyoto Protocol Reference Manual on Accounting of Emissions and Assigned Amount.”
West, T., et al. (2023). “Analysis of Rainforest Carbon Offset Certification.” Nature Climate Change, 13(1).