What is the story of the dispute between Ali and Mu'awiyah, may Allah be pleased with them, and what was the reason for Abu Dharr's objection to Uthman's and Mu'awiyah's handling of the Muslims' wealth?

To learn about what happened between Ali and Mu'awiyah, it is recommended to refer to reliable historical texts such as "Al-Bidayah wa al-Nihayah" (The Beginning and the End) and "Tarikh al-Tabari" (The History of al-Tabari).

The reason for Abu Dharr's dissatisfaction with Mu'awiyah and Uthman's handling of the Muslims' wealth was his view that any surplus beyond essential expenses must be given in charity, citing the verse: "And those who hoard gold and silver and do not spend it in the way of Allah – give them tidings of a painful punishment."

The rest of the Companions disagreed with him on this, believing that "hoarding" referred to wealth upon which zakat had not been paid. Their evidence was a hadith from Ibn Abbas in which the Prophet, peace and blessings be upon him, said: "Indeed, Allah did not ordain zakat except to purify what remained of your wealth." The correct view, upon which the majority stands, is that hoarding refers to wealth upon which zakat has not been paid; if its zakat is paid, then it is not considered hoarding.