Muhammad ibn Ya'qub, in mursal form, from Yunus ibn Abd al-Rahman, from Ali ibn Abi Hamzah, from Abu Basir, from Abu Abdillah عليه السلام, peace be upon him, who said: Imam عليه السلام said: "Whoever withholds a ‘qirat’ (a tiny fraction of wealth) from the zakat is neither a believer nor a Muslim, and this is His عز وجل saying, Mighty and Majestic: 'My Lord عز وجل, return me, so that I may do righteousness in what I left behind.'" (Surah al-Mu’minun 23:99-100)