Why do you consider bonds usury?

In many historical societies, religious prohibitions on usury meant the charging of interest of any kind.

Jump in a time machine to 1515 and ask Martin Luther, or to 1260 and ask Thomas Aquinas, they'd tell you it's sinful.

And in the present age, a fair number of Islamic folk consider interest against their religion's rules. So there's a Halal finance industry where, for example, you can get a "murabahah contract" where the bank buys a house, then sells the house to you at a higher price, while allowing you to pay them in monthly instalments.

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