The Ways of Ascent - 70:24
A known portion (zakat) has been set aside in their money,
Known share:
The Cow/2:219
"They ask you about intoxicants and gambling: Say: "There is a great sin in both of them and benefits for mankind, but their sin is greater than their benefit."They also ask you what they should give in charity: Say, "The surplus."This is how Allah explains His verses so that you may reflect"
يَسْـَٔلُونَكَ عَنِ الْخَمْرِ وَالْمَيْسِرِۜ قُلْ ف۪يهِمَٓا اِثْمٌ كَب۪يرٌ وَمَنَافِـعُ لِلنَّاسِۘ وَاِثْمُهُمَٓا اَكْبَرُ مِنْ نَفْعِهِمَاۜ وَيَسْـَٔلُونَكَ مَاذَا يُنْفِقُونَۜ قُلِ الْعَفْوَۜ كَذٰلِكَ يُبَيِّنُ اللّٰهُ لَكُمُ الْاٰيَاتِ لَعَلَّكُمْ تَتَفَكَّرُونَۙ