Since I first started writing about art and money almost 11 years ago, one lesson that people’s reactions have reinforced over and over again is that the tensions between the two forces tend to be thought of as relatively recent phenomena. In reality, the truth is that they are anything but. A brilliant exhibition at the Morgan Library and Museum in New York elucidates that people have been vexed by the tensions between visual art and the monetary economy for as long as the latter has existed.

Titled Medieval Money, Merchants and Morality (until 10 March), the show turns works of art, manuscripts and other objects into a prism to examine the economic revolution that took place in western Europe from the 13th to the 16th centuries—and vice versa. The unifying conceit is that money functioned as what Diane Wolfthal, a professor emerita of art history at Houston’s Rice University and the show’s guest curator, calls a “new medium” whose purpose, proper use and consequences were all being debated by people up and down the financial hierarchy, from Italy and England to the Low Countries, with art becoming a vital piece of the conversation.

I want to focus on three particular ways that works of art played into the metabolising of the new monetary economy during this period: as a visual record of the new developments, as an instruction manual about how to think through the tensions they raised and as an arena in which people and institutions wrestled with their own doubts about the morality of money.

Money matters

The Middle Ages and Renaissance saw multiple economic innovations that laid the groundwork for modern capitalism, starting with the production of low-value coins for everyday trade. Prior to this, the dominant mode of exchange was the bartering of goods or services—say, trading a chicken for three heads of cabbage—since “most stores of value were in people’s homes, land, textiles, furs, fish and other things”, says Deirdre Jackson, the assistant curator of Medieval and Renaissance manuscripts at the Morgan.

But low-value coins also created several problems. For starters, they were all handmade, limiting their production while also meaning that, even in the best times, each coin was slightly irregular in form, size and weight. Worse, even the imperfect standards for these coins tended to erode based on the availability (or scarcity) of their raw materials. “In general most types of Medieval coins gradually declined in precious metal content over time—by being made lighter, by alloying the silver or gold with cheaper metals, or both,” the scholar Steven Yoon writes in the exhibition catalogue.

Despite being royally sanctioned, the minting of coins was also typically a for-profit business run at a local or regional level. This fact meant that dozens and dozens of currencies cropped up throughout the region now known as Europe. Italy, for instance, at various points gave rise to the Venetian torneselli, the Florentine florin and the Bolognese doppio ducato, among others. For trade networks to expand, the abundance of currencies necessitated currency exchanges. Operating them was only possible if people in one location were keeping close tabs on how the coin supply was changing elsewhere.

This new form of interconnection through money became so ever-present that it even infiltrated some religious texts. On view in the exhibition is St Gregory the Great and Coins, a page in the Hours of Catherine of Cleves, an illuminated manuscript made in Utrecht around 1440. The central image depicts the titular saint in full regalia against a red-patterned background and gold-leaf chequered floor. But much more interesting is what borders the image and text: 25 representations of eight actual coins from the Netherlands, Germany and Denmark that would have circulated through Utrecht in the early 15th century. (The one exception is the Danish penny, which appears six times on the right side of the page despite not being in wide use there, Wolfthal writes in the exhibition catalogue.)

The artist’s rendering of the coins is impressively illusionistic. The images largely replicate the iconography and text that adorned the front and back of the various coins, as well as their relative sizes and the colours of the metals they were made of. The irregularity caused by the coins’ handcrafting is also evident in their contours, making the page almost as much a historical document as a work of art.

There are multiple hypotheses about why the artist behind the manuscript paired St Gregory with the border of coins. Most revolve around his generosity to the poor (and his willingness to live simply to enable it). But one especially interesting theory is that, after being appointed pope in 590, the man who would become St Gregory established, in Wolfthal’s words, “a very effective administrative system of channelling donations to the Church to support the poor, especially refugees in Rome fleeing the violence of the Lombards”, who had seized much of Italy during his reign.

Regardless of the exact motivation, St Gregory the Great and Coins indicates that money and morality were already tied together in complex ways more than half a millennium ago. And that’s just one example of one interplay between these forces.

Beyond cash, beyond sin

Despite the rise of currency exchanges, carrying physical money from place to place was difficult and risky in the Middle Ages, and it only became more so as commerce incentivised people to travel greater and greater distances. Coins were heavy in large quantities, and thieves were plentiful. Not surprisingly, people were not thrilled by either the extra costs of hiring others to lug strongboxes full of metal and fight off brigands, or the strain and perils of doing both themselves.

These headaches catalysed financial innovations. Vital among them was the bill of exchange, a slip of paper written by a banker or a merchant in one place and time that guaranteed payment to the bearer elsewhere, later, in a different currency. Yoon calls the bill of exchange both “an adaptation to the extreme complexities of Medieval coinage systems” and “one of the harbingers of a new system of banks, credit, paper currency and virtual money that exists only as numbers in accounts”.

In other words, the bill of exchange initiated the ways we understand money today. But it also exacerbated the ways we agonise over it, too.

Consider the moral dilemma facing merchants and bankers, both of whom were able to achieve levels of wealth previously exclusive to royalty and the Church courtesy of the new monetary economy. Their chief spiritual problem was their perception as usurers. Initially defined as the practice of charging interest on a loan to members of your own faith, usury stemmed from the belief that making money “reproduce” on its own was unnatural—an idea that dated back to Aristotle. The only truly moral profits, in contrast, came from manual labour. “If you made money in any way through investment, you had tremendous guilt and were worried you were going to hell,” Wolfthal says.

The new financiers set out to counteract this problem partly through visual art, in more ways than one. First, they used their wealth to fund or donate religious works of art as a form of penance. Examples include the Paduan money-lender Enrico Scrovegni commissioning Giotto to paint the frescoes of the Arena Chapel, and the Florentine banker Cosimo de’ Medici paying for the frescoes made to adorn the San Marco religious complex in his hometown.

But bankers and merchants also tried to reshape perceptions of their professions through visual language, even on a personal scale. For instance, the Morgan exhibition includes Jan Gossart’s Portrait of a Merchant (around 1530), which goes to great lengths to portray its sitter as an honourable workingman rather than an idle (and thus immoral) plutocrat. It contains minimal visible signs of wealth; aside from the subject’s clothing and rings, there are only a few coins scattered on the desk—notably, to be weighed on the balance atop them as a part of his job.

Gossart’s subject appears to have only looked up momentarily from updating his ledger. Suspended behind him are two sheafs of work-related documents (the cover-page scripts read “miscellaneous drafts” and “miscellaneous letters”). His desk is blanketed by an array of unglamorous mercantile instruments and office necessities: an inkwell and blotter, tape, scissors, twine and a modest candle-holder. All of these elements feed into the notion that this merchant is genuinely labouring in a manner befitting the Church’s ideal. Basically, it’s all a way of communicating, “Hey, even though I work in this field you’re suspicious of, I’m a good guy!” In this sense, it functions as a kind of instruction manual for how to live as a part of the new financial class.

Works of art also served as more literal instruction manuals. Covetousness, a page from an illuminated version of the chivalric poem Le roman de la rose (the romance of the rose) made around 1350, anthropomorphises the sin as a woman grabbing money bags out of coffers stacked with gold objects and silver coins. The conceit of the poem’s opening section is that a man searching for his beloved must overcome a variety of moral failings along the way—many of them involving wealth. In addition to Covetousness, they include Avarice and Envy, with each depiction premised in one way or another on riches (or want of them). Together, the poem and its imagery, which proliferated across Europe during the Middle Ages, offered central lessons for people grappling with the ethical challenges of the new economy.

Reverse-engineering the faith

Crucially, none of the efforts by merchants and bankers to revise their images would have mattered had the Church itself not gone along with the revisionism. Fortunately for the financial class, however, there was too much opportunity for religious institutions to do anything else. “The main thing I saw changing over time is that the Church gradually acclimated to capitalism,” Wolfthal says of the period covered by the exhibition.

The Church “originally came down very hard on usury”, adds Wolfthal, who first came to this subject roughly 20 years ago while teaching a course on mercantile culture. She writes in the exhibition catalogue that the overarching belief during the Middle Ages and Renaissance was that there were only three “fruitful” uses of money: “meeting the needs of one’s family, the poor and the Christian community”.

But the last of these took a momentous turn as theologians gradually redefined the boundaries of morality vis-à-vis the economic revolution. Enter the purchase of indulgences, payments that the Church channelled into public works and, supposedly, neutralising the sins of the benefactor.

Indulgences were an invention as ingenious as they were disruptive to the faith. Spiritually, the exchange was simple: the more money a person gave, the more of their moral failings would be scrubbed away—and thus the better their odds of entering heaven would become. Practically, indulgences helped strengthen the Church’s influence by funding the construction of valued spaces such as hospitals, lepers’ sanctuaries and (of course) new and improved cathedrals during a time when the collection of secular taxes and corresponding civic maintenance and improvement projects were still nascent and rare.

Prior to the emergence of the monetary economy, indulgences were typically granted only in exchange for good works or military service in the Crusades. Afterward, however, their expansion into the economic system meant that salvation could be bought and sold, an audacious turn for a faith ostensibly premised on virtue’s supremacy over wealth and earthly power.

Indulgences also made the Church a key cog in the nascent international network of finance, as believers could purchase them in one place to support projects sited in another city or country hundreds of miles away. Jackson, for instance, mentions one indulgence scheme offered in London to help fund the construction of St Peter’s Basilica in Rome.

Although these changes were officially sanctioned, not everyone was comfortable with them. Multiple works in the Morgan exhibition embody the doubts some patrons and artists harboured about the Church’s embrace of capitalism. Take, for example, St Francis Renouncing His Worldly Goods, painted around 1500 by an unknown artist (possibly the Master of St Augustine, possibly in Antwerp). Although it tells the familiar story of the titular saint opting for poverty and God over his middle-class existence as the son of a textile merchant, the painting also seems to criticise the Church’s entanglement with money. In the centre of the canvas, we see Francis stripping off his fine clothes in front of a bishop dripped out in gold, jewels and opulent vestments. The bishop and his attendants look mortified by Francis’s choice; the bishop even has one gloved, ringed hand on Francis’s arm, as if imploring him to stop.

The imagery seems damning enough without further context. But it only becomes more so given that versions of this scene were not uncommon in everyday life by the turn of the 16th century in Europe. The reason is that the Church, which had earlier deemed usurers to be sinners, later declared it sinful for borrowers not to repay their debts. In fact, when lenders wanted their money back, they sometimes dragged debtors in front of ecclesiastical officials, who could seize the debtor’s goods—including the clothes off their backs—by the authority of the Church.

Medieval Money, Merchants and Morality brims with other works reflecting the contortions the monetary economy put the people of Europe through during the Middle Ages and Renaissance. Along with the objects that track the emergence of capitalism in less complicated ways, they capture that art’s collision with money has been confronting humanity with questions about what is good and right for hundreds of years. That we as a species are still debating their proper relationship in the 2020s proves that there will never be broad agreement on where the boundaries should be—and that’s fine, as long as we don’t fool ourselves into believing otherwise. On this subject, even the Medieval Church wasn’t holier than thou.

• Medieval Money, Merchants and Morality, until 10 March, Morgan Library and Museum, New York