Where there is no fixed judgement, the traditions and conventions of community are to be referred
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ حُمَيْدٍ الطَّوِيلِ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ قَالَ حَجَمَ رَسُولَ اللَّهِ صلى الله عليه وسلم أَبُو طَيْبَةَ، فَأَمَرَ لَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم بِصَاعٍ مِنْ تَمْرٍ، وَأَمَرَ أَهْلَهُ أَنْ يُخَفِّفُوا عَنْهُ مِنْ خَرَاجِهِ.
Narrated Anas bin Malik: Abu Taiba cupped Allah's Messenger (ﷺ) and so Allah's Messenger (ﷺ) ordered that a Sa of dates be paid to him and ordered his masters (for he was a slave) to reduce his tax.