Sunan Abi Dawud, Hadith 2640

Ibn ‘Abbas said “When the verse “If there are twenty amongst you patient and persevering, they will vanquish two hundred” was revealed. It was heavy and troublesome for Muslims when Allaah prescribed for them that one (fighting Muslim) should not fly from ten (fighting Non-Muslims). Then a light commandment was revealed saying “For the present Allaah hath lightened your (task).” The narrator Abu Tawbah recited the verse to “they will vanquish two hundred.” When Allaah lightened the number, patient and perseverance also decreased according to the number lightened from them.”

حَدَّثَنَا أَبُو تَوْبَةَ الرَّبِيعُ بْنُ نَافِعٍ، حَدَّثَنَا ابْنُ الْمُبَارَكِ، عَنْ جَرِيرِ بْنِ حَازِمٍ، عَنِ الزُّبَيْرِ بْنِ خِرِّيتٍ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَزَلَتْ ‏{‏ إِنْ يَكُنْ مِنْكُمْ عِشْرُونَ صَابِرُونَ يَغْلِبُوا مِائَتَيْنِ ‏}‏ فَشَقَّ ذَلِكَ عَلَى الْمُسْلِمِينَ حِينَ فَرَضَ اللَّهُ عَلَيْهِمْ أَنْ لاَ يَفِرَّ وَاحِدٌ مِنْ عَشَرَةٍ ثُمَّ إِنَّهُ جَاءَ تَخْفِيفٌ فَقَالَ ‏{‏ الآنَ خَفَّفَ اللَّهُ عَنْكُمْ ‏}‏ قَرَأَ أَبُو تَوْبَةَ إِلَى قَوْلِهِ ‏{‏ يَغْلِبُوا مِائَتَيْنِ ‏}‏ قَالَ فَلَمَّا خَفَّفَ اللَّهُ تَعَالَى عَنْهُمْ مِنَ الْعِدَّةِ نَقَصَ مِنَ الصَّبْرِ بِقَدْرِ مَا خَفَّفَ عَنْهُمْ ‏.‏

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also referenced under: Hadith 2646 (DarusSalam)