This point is spelt out in Deuteronomy: “Every creditor that lendeth ought unto his neighbour shall release it; he shall not exact it of his neighbour, or of his brother; because it is called the Lord's release.”

Such injunctions may strike the modern reader as utopian. How could any sophisticated society function if all debts were cancelled twice a century – much less, as Deuteronomy seems to suggest, every seven years? Yet we know that such general cancellations of debt really did happen in the ancient world. In 1788 BC, for example, about 500 years before the time of Moses, King Rim-Sin of Ur issued a royal edict declaring all loans null and void, wiping out some of history's earliest known moneylenders.

The idea of a generalised debt cancellation is not wholly unknown in modern times. The late Gerald Feldman, the world's leading authority on the German hyperinflation of 1923, drew a parallel between the ancient Hebrew yovel and the wiping out of all paper mark-denominated debts as a result of the collapse of the German currency (though, as he was quick to point out, those whose savings were wiped out were far from jubilant).