I went to Abu Wail to ask him (about those who had rebelled against ʿAli). On that Abu Wail said, "We were at Siffin (a city on the bank of the Euphrates, the place where me battle took place between ʿAli and Muawiya) A man said, "Will you be on the side of those who are called to consult Allah's Book (to settle the dispute)?" ʿAli said, 'Yes (I agree that we should settle the matter in the light of the Qur'an)." ' Some people objected to ʿAli's agreement and wanted to fight. On that Sahl bin Hunaif said, 'Blame yourselves! I remember how, on the day of Al-Hudaibiya (i.e. the peace treaty between the Prophet ﷺ and the Quraish pagans), if we had been allowed to choose fighting, we would have fought (the pagans). At that time ʿUmar came (to the Prophet) and said, "Aren't we on the right (path) and they (pagans) in the wrong? Won't our killed persons go to Paradise, and theirs in the Fire?" The Prophet replied, "Yes." ʿUmar further said, "Then why should we let our religion be degraded and return before Allah has settled the matter between us?" The Prophet ﷺ said, "O the son of Al-Khattab! No doubt, I am Messenger of Allah ﷺ and Allah will never neglect me." So ʿUmar left the place angrily and he was so impatient that he went to Abu Bakr and said, "O Abu Bakr! Aren't we on the right (path) and they (pagans) on the wrong?" Abu Bakr said, "O the son of Al-Khattab! He is Messenger of Allah ﷺ, and Allah will never neglect him." Then Sura Al-Fath (The Victory) was revealed."  

رَجُلٌ أَلَمْ تَرَ إِلَى الَّذِينَ يُدْعَوْنَ إِلَى كِتَابِ اللَّهِ فَقَالَ عَلِيٌّ نَعَمْ فَقَالَ سَهْلُ بْنُ حُنَيْفٍ اتَّهِمُوا أَنْفُسَكُمْ فَلَقَدْ رَأَيْتُنَا يَوْمَ الْحُدَيْبِيَةِ يَعْنِي الصُّلْحَ الَّذِي كَانَ بَيْنَ النَّبِيِّ ﷺ وَالْمُشْرِكِينَ وَلَوْ نَرَى قِتَالاً لَقَاتَلْنَا فَجَاءَ عُمَرُ فَقَالَ أَلَسْنَا عَلَى الْحَقِّ وَهُمْ عَلَى الْبَاطِلِ أَلَيْسَ قَتْلاَنَا فِي الْجَنَّةِ وَقَتْلاَهُمْ فِي النَّارِ قَالَ بَلَى قَالَ فَفِيمَ أُعْطِي الدَّنِيَّةَ فِي دِينِنَا وَنَرْجِعُ وَلَمَّا يَحْكُمِ اللَّهُ بَيْنَنَا فَقَالَ يَا ابْنَ الْخَطَّابِ إِنِّي رَسُولُ اللَّهِ وَلَنْ يُضَيِّعَنِي اللَّهُ أَبَدًا فَرَجَعَ مُتَغَيِّظًا فَلَمْ يَصْبِرْ حَتَّى جَاءَ أَبَا بَكْرٍ فَقَالَ يَا أَبَا بَكْرٍ أَلَسْنَا عَلَى الْحَقِّ وَهُمْ عَلَى الْبَاطِلِ قَالَ يَا ابْنَ الْخَطَّابِ إِنَّهُ رَسُولُ اللَّهِ ﷺ وَلَنْ يُضَيِّعَهُ اللَّهُ أَبَدًا فَنَزَلَتْ سُورَةُ الْفَتْحِ  

Sahal b. Hunaif stood up on the Day of Siffin and said: O ye people, blame yourselves (for want of discretion) ; we were with the Messenger of Allah ﷺ on the Day of Hudaibiya. If we had thought it fit to fight, we could fight. This was in the truce between the Messenger of Allah ﷺ and the polytheists. Umar b. Khattab came, approached the Messenger of Allah ﷺ and said: Messenger of Allah, aren't we fighting for truth and they for falsehood? He replied: By all means. He asked: Are not those killed from our side in Paradise and those killed. from their side in the Fire? He replied: Yes. He said: Then why should we put a blot upon our religion and return, while Allah has not decided the issue between them and ourselves? He said: Son of Khattab, I am the Messenger of Allah. Allah will never ruin me. (The narrator said): Umar went away, but he could not contain himself with rage. So he approached Abu Bakr and said: 'Abu Bakr, aren't we fighting for truth and they for falsehood? He replied: Yes. He asked: Aren't those killed from our side in Paradise and those killed from their side in the Fire? He replied: Why not? He (then) said: Why should we then disgrace our religion and return while God has not yet decided the issue between them and ourselves? Abu Bakr said: Son of Khattab, verily, he is the Messenger of Allah, and Allah will never ruin him. (The narrator continued): At this (a Sura of) the Qur'an (giving glad tidings of the victory) was revealed to the Messenger of Allah ﷺ. He sent for Umar and made him read it. He asked: Is (this truce) a victory? He (the Messenger of Allah) replied: Yes. At this Umar was pleased, and returned.  

أَيُّهَا النَّاسُ اتَّهِمُوا أَنْفُسَكُمْ لَقَدْ كُنَّا مَعَ رَسُولِ اللَّهِ ﷺ يَوْمَ الْحُدَيْبِيَةِ وَلَوْ نَرَى قِتَالاً لَقَاتَلْنَا وَذَلِكَ فِي الصُّلْحِ الَّذِي كَانَ بَيْنَ رَسُولِ اللَّهِ ﷺ وَبَيْنَ الْمُشْرِكِينَ فَجَاءَ عُمَرُ بْنُ الْخَطَّابِ فَأَتَى رَسُولَ اللَّهِ ﷺ فَقَالَ يَا رَسُولَ اللَّهِ أَلَسْنَا عَلَى حَقٍّ وَهُمْ عَلَى بَاطِلٍ قَالَ بَلَى قَالَ أَلَيْسَ قَتْلاَنَا فِي الْجَنَّةِ وَقَتْلاَهُمْ فِي النَّارِ قَالَ بَلَى قَالَ فَفِيمَ نُعْطِي الدَّنِيَّةَ فِي دِينِنَا وَنَرْجِعُ وَلَمَّا يَحْكُمِ اللَّهُ بَيْنَنَا وَبَيْنَهُمْ فَقَالَ يَا ابْنَ الْخَطَّابِ إِنِّي رَسُولُ اللَّهِ وَلَنْ يُضَيِّعَنِي اللَّهُ أَبَدًا قَالَ فَانْطَلَقَ عُمَرُ فَلَمْ يَصْبِرْ مُتَغَيِّظًا فَأَتَى أَبَا بَكْرٍ فَقَالَ يَا أَبَا بَكْرٍ أَلَسْنَا عَلَى حَقٍّ وَهُمْ عَلَى بَاطِلٍ قَالَ بَلَى قَالَ أَلَيْسَ قَتْلاَنَا فِي الْجَنَّةِ وَقَتْلاَهُمْ فِي النَّارِ قَالَ بَلَى قَالَ فَعَلاَمَ نُعْطِي الدَّنِيَّةَ فِي دِينِنَا وَنَرْجِعُ وَلَمَّا يَحْكُمِ اللَّهُ بَيْنَنَا وَبَيْنَهُمْ فَقَالَ يَا ابْنَ الْخَطَّابِ إِنَّهُ رَسُولُ اللَّهِ وَلَنْ يُضَيِّعَهُ اللَّهُ أَبَدًا قَالَ فَنَزَلَ الْقُرْآنُ عَلَى رَسُولِ اللَّهِ ﷺ بِالْفَتْحِ فَأَرْسَلَ إِلَى عُمَرَ فَأَقْرَأَهُ إِيَّاهُ فَقَالَ يَا رَسُولَ اللَّهِ أَوَفَتْحٌ هُوَ قَالَ نَعَمْ فَطَابَتْ نَفْسُهُ وَرَجَعَ  

Sahal b. Hunaif stood up on the Day of Siffin and said: O ye people, blame yourselves (for want of discretion) ; we were with the Messenger of Allah ﷺ on the Day of Hudaibiya. If we had thought it fit to fight, we could fight. This was in the truce between the Messenger of Allah ﷺ and the polytheists. Umar b. Khattab came, approached the Messenger of Allah ﷺ and said: Messenger of Allah, aren't we fighting for truth and they for falsehood? He replied: By all means. He asked: Are not those killed from our side in Paradise and those killed. from their side in the Fire? He replied: Yes. He said: Then why should we put a blot upon our religion and return, while Allah has not decided the issue between them and ourselves? He said: Son of Khattab, I am the Messenger of Allah. Allah will never ruin me. (The narrator said): Umar went away, but he could not contain himself with rage. So he approached Abu Bakr and said: 'Abu Bakr, aren't we fighting for truth and they for falsehood? He replied: Yes. He asked: Aren't those killed from our side in Paradise and those killed from their side in the Fire? He replied: Why not? He (then) said: Why should we then disgrace our religion and return while God has not yet decided the issue between them and ourselves? Abu Bakr said: Son of Khattab, verily, he is the Messenger of Allah, and Allah will never ruin him. (The narrator continued): At this (a Sura of) the Qur'an (giving glad tidings of the victory) was revealed to the Messenger of Allah ﷺ. He sent for Umar and made him read it. He asked: Is (this truce) a victory? He (the Messenger of Allah) replied: Yes. At this Umar was pleased, and returned. (Using translation from Muslim 1785a)   

أَنَّهُ قَالَ يَوْمَ صِفِّينَ أَيُّهَا النَّاسُ اتَّهِمُوا أَنْفُسَكُمْ وَلَقَدْ رَأَيْتُنَا يَوْمَ الْحُدَيْبِيَةِ وَلَوْ نَرَى قِتَالًا لَقَاتَلْنَاهُمْ فَقَالَ عُمَرُ يَا رَسُولَ اللهِ أَلَسْنَا عَلَى حَقٍّ وَهُمْ عَلَى بَاطِلٍ؟ أَلَيْسَ قَتْلَانَا فِي الْجَنَّةِ وَقَتْلَاهُمْ فِي النَّارِ؟ قَالَ «بَلَى» قَالَ فَفِيمَ نُعْطِي الدَّنِيَّةَ فِي دِينِنَا وَنَرْجِعُ وَلَمَّا يَحْكُمِ اللهُ بَيْنَنَا وَبَيْنَهُمْ؟ قَالَ «يَا ابْنَ الْخَطَّابِ إِنِّي رَسُولُ اللهِ وَلَنْ يُضَيِّعَنِي أَبَدًا» فَرَجَعَ وَهُوَ مَغِيظٌ وَلَمْ يَصْبِرْ حَتَّى أَتَى أَبَا بَكْرٍ فَقَالَ أَلَسْنَا عَلَى حَقٍّ وَهُمْ عَلَى بَاطِلٍ؟ أَلَيْسَ قَتْلَانَا فِي الْجَنَّةِ وَقَتْلَاهُمْ فِي النَّارِ؟ قَالَ بَلَى قَالَ فَفِيمَ نُعْطِي الدَّنِيَّةَ فِي دِينِنَا فَنَرْجِعُ وَلَمَّا يَحْكُمِ اللهُ بَيْنَنَا وَبَيْنَهُمْ؟ فَقَالَ يَا ابْنَ الْخَطَّابِ إِنَّهُ رَسُولُ اللهِ وَلَنْ يُضَيِّعَهُ اللهُ أَبَدًا فَنَزَلَتْ سُورَةُ الْفَتْحِ فَأَرْسَلَ رَسُولُ اللهِ ﷺ إِلَى عُمَرَ فَأَقْرَأَهُ إِيَّاهَا فَقَالَ يَا رَسُولَ اللهِ أَفْتَحٌ هُوَ؟ قَالَ «نَعَمْ»