Sunan an-Nasa'i, Volume 3, Book 23, Hadith 2510 (DarusSalam) ⓘ

When he was the governor of Al-Basrah, at the end of the month, Ibn 'Abbas said: "Give Zakah of your fast." The people looked at one another, so he said: "Whoever is here from the people of Al-Madinah, get up and teach your brothers, for they do lnot know that this Zakah was enjoined by the Messenger of Allah upon every male and female, free and slave, a Sa' of barley or dates, or half a Sa' of wheat. "So they got up. (Da'if) Hisham contradicted him, he said: "From Muhammad bin Sirin."

أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، قَالَ حَدَّثَنَا خَالِدٌ، - وَهُوَ ابْنُ الْحَارِثِ - قَالَ حَدَّثَنَا حُمَيْدٌ، عَنِ الْحَسَنِ، قَالَ قَالَ ابْنُ عَبَّاسٍ وَهُوَ أَمِيرُ الْبَصْرَةِ فِي آخِرِ الشَّهْرِ أَخْرِجُوا زَكَاةَ صَوْمِكُمْ ‏.‏ فَنَظَرَ النَّاسُ بَعْضُهُمْ إِلَى بَعْضٍ فَقَالَ مَنْ هَا هُنَا مِنْ أَهْلِ الْمَدِينَةِ قُومُوا فَعَلِّمُوا إِخْوَانَكُمْ فَإِنَّهُمْ لاَ يَعْلَمُونَ إِنَّ هَذِهِ الزَّكَاةَ فَرَضَهَا رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى كُلِّ ذَكَرٍ وَأُنْثَى حُرٍّ وَمَمْلُوكٍ صَاعًا مِنْ شَعِيرٍ أَوْ تَمْرٍ أَوْ نِصْفَ صَاعٍ مِنْ قَمْحٍ ‏.‏ فَقَامُوا ‏.‏ خَالَفَهُ هِشَامٌ فَقَالَ عَنْ مُحَمَّدِ بْنِ سِيرِينَ ‏.‏