How much damage is one permitted to wreak against a fellow Jew who called him wicked?
On Daf 71a it says that if a person calls a fellow Jew wicked he may go down to his livelihood, and Tosfos brings the explanation of Rav Tzaddok Gaon that the gemora means that he is permitted to burn a third of his produce (שליש תבואתו). But Tosfos asks in astonishment from where did Rav Tzaddok learn this?
But we can explain that when Rav Tzaddok says שליש תבואתו he means all of his produce which is a third of all his wealth - as R. Yitzchok taught on Daf 42a “A person should divide up his wealth into three parts: one part in the land, one part in merchandise, and one part in liquid capital”. That is why Rav Tzaddok said שליש תבואתו, which means "a third - his produce", and did not say שליש מתבואתו, which would have meant "a third of his produce".