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حَدَّثَنَا حُمَيْدُ بْنُ مَسْعَدَةَ حَدَّثَنَا سُفْيَانُ بْنُ حَبِيبٍ عَنْ ثَوْرِ بْنِ يَزِيدَ عَنْ خَالِدِ بْنِ مَعْدَانَ عَنْ عَبْدِ اللَّهِ بْنِ بُسْرٍ عَنْ أُخْتِهِأَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ لَا تَصُومُوا يَوْمَ السَّبْتِ إِلَّا فِيمَا افْتَرَضَ اللَّهُ عَلَيْكُمْ فَإِنْ لَمْ يَجِدْ أَحَدُكُمْ إِلَّا لِحَاءَ عِنَبَةٍ أَوْ عُودَ شَجَرَةٍ فَلْيَمْضُغْهُقَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ وَمَعْنَى كَرَاهَتِهِ فِي هَذَا أَنْ يَخُصَّ الرَّجُلُ يَوْمَ السَّبْتِ بِصِيَامٍ لِأَنَّ الْيَهُودَ تُعَظِّمُ يَوْمَ السَّبْتِ

Narrated to us [Humaid bin Mas'adah] narrated to us [Sufyan bin Habib] from [Tsaur bin Yazid] from [Khalid bin Ma'dan] from [Abdullah bin Busr] from [his sister] that the Messenger of Allah peace and blessings be upon him said: 'Do not fast only on Saturday except if Allah obligates fasting on that day, if on that day you do not find except a grape or a tree branch then chew it.' Abu 'Isa said, this is a hasan hadith. The meaning of disliking fasting on Saturday is if he specifies fasting on Saturday, because the Jews glorify Saturday."