There's no difference at all between what WAS called usury and what's NOW called capitalism (or speculation or banking or just plain business).
But back before a supposedly representative blizzard of paper and blather obscured our view of what money supposedly represented - the exchange of labor for product or product for labor or labor for labor or product for product - usury, which was simply the tricky trading of IOU's and promises to get too much of this for too little of that, was such a clear and flagrant violation of the social contract and so routinely condemned that even the gods forbade it as a sin.
And why not? Capitalism or usury or whatever you call it is an effort to make a profit, to get more than one gives and, thus, clearly, to cheat. Unsophisticated neolithic men new to community organizing but willing to get involved, were willing (or the worth-a-damn smart ones were willing) because, unlike the competitive jungle savagery they were used to, sensibly cooperative civilization utilizing a sensibly civilized economic system was less painfully fair. But usury, capitalism, free enterprise, whatever you call it (which came along as soon as a few pigs figured out how to work the system for their own benefit) is criminally unfair.
So, in justifiably angry reaction to the pigs, usury became a 5-letter word, but time passed, shit happened, and by the time the WORD had become irredeemable, the ACT became, in fact, the common trade of people with too much influence and power to be conveniently disrespected.
Then, as more time went by, the WORD usury was mummified, along with other odd old words like covetousness and gluttony, and pressed like a bug between the pages of old black bibles where it could be ceremonially shunned every Sunday by churchgoing capitalists as one of those olden-days sins their god ordered them to shun.
But if you look it up in the Dartmouth Bible or in Webster's, you'll find that usury was capitalism and capitalism is usury.
2.The law of the jungle extended into town.