Religion, usury & interest

For most of recorded history, lending money at interest wasn’t just frowned upon — it was a sin. Understanding that prohibition, and how one community ended up carrying it, explains both the roots of banking and the origin of a persistent and harmful stereotype.

What is usury?

Originally, “usury” meant charging any interest at all on a loan — not merely excessive interest, as the word implies today. Lending your neighbour a coin and demanding back more than you gave was seen as profiting from their need without doing any work: making money from money.

Every major faith condemned it

• Christianity — the medieval Church forbade Christians from lending to other Christians at interest, citing scripture and reinforcing it at councils. A usurer could be denied a Christian burial.
• Islam — prohibits “riba” (interest) outright, to this day. Modern Islamic finance is built specifically to avoid it, using profit-sharing instead of lending at interest.
• Judaism — the Torah forbids charging interest to a fellow Jew, but permits lending to an outsider at interest. So Jewish law didn’t ban interest universally; it banned it within the community.

How a whole people got pushed into lending

Here is the part usually told wrong. In much of medieval Christian Europe, Jews were barred from owning land, joining craft guilds, and entering most respectable professions. One of the few livelihoods left open to them was the one Christians were forbidden to do: lending money at interest.

So a structural situation emerged. Christians needed credit — to trade, to fight wars, to build — but couldn’t lend to each other. Jews were excluded from almost everything else and permitted (by their own law) to lend to non-Jews. Rulers found this convenient: they could borrow from Jewish lenders, and when debts came due, they could expel or persecute the lenders and cancel what they owed.

Why the taboo faded

As commerce expanded in the Renaissance, the moral line softened. Thinkers began to distinguish reasonable interest — compensation for risk and for the time your money is tied up — from exploitative “usury”. Christian banking houses (the Medici and others) found workarounds, and eventually lending at interest became the ordinary basis of finance. Once the taboo broke, the door was open to the institutions that dominate the rest of this story: paper claims on gold, and banks that lend far more than they hold.