ذِكْرُ الْإِبَاحَةِ لِلْمَرْءِ أَنْ يُخْرِجَ فِي زَكَاةِ الْفِطْرِ صَاعَ أَقِطٍ
"We used to pay Salaqatul Fitr when the Messenger of Allah was among us; a Sa' of food, or a Sa' of dates, or a Sa' of barley, or a Sa' of cottage cheese. We continued to do so until Mu'awiyah came from Ash-Sham and one of the things that he taught the people was when he said: I think that two Mudds of wheat from Ash-Sham are equivalent to a Sa' of this, So the people took to that." (Using translation from Nasāʾī 2513)
كُنَّا نُخْرِجُ فِي صَدَقَةِ الْفِطْرِ إِذْ كَانَ فِينَا رَسُولُ اللَّهِ ﷺ صَاعًا مِنْ طَعَامٍ أَوْ صَاعًا مِنْ تَمْرٍ أَوْ صَاعًا مِنْ شَعِيرٍ أَوْ صَاعًا مِنْ أَقِطٍ وَلَمْ نَزَلْ كَذَلِكَ حَتَّى قَدِمَ عَلَيْنَا مُعَاوِيَةُ مِنَ الشَّامِ إِلَى الْمَدِينَةِ قَدْمَةً فَكَانَ فِيمَا كَلَّمَ بِهِ النَّاسَ «مَا أَرَى مُدَّيْنِ مِنْ سَمْرَاءِ الشَّامِ إِلَّا تَعْدِلُ صَاعًا مِنْ هَذِهِ» فَأَخَذَ النَّاسُ بِذَلِكَ