حَدَّثَنَا حَفْصُ بْنُ عُمَرَ النَّمَرِيُّ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي الْفَيْضِ، عَنْ سُلَيْمِ بْنِ عَامِرٍ، - رَجُلٍ مِنْ حِمْيَرَ - قَالَ كَانَ بَيْنَ مُعَاوِيَةَ وَبَيْنَ الرُّومِ عَهْدٌ وَكَانَ يَسِيرُ نَحْوَ بِلاَدِهِمْ حَتَّى إِذَا انْقَضَى الْعَهْدُ غَزَاهُمْ فَجَاءَ رَجُلٌ عَلَى فَرَسٍ أَوْ بِرْذَوْنٍ وَهُوَ يَقُولُ اللَّهُ أَكْبَرُ اللَّهُ أَكْبَرُ وَفَاءٌ لاَ غَدْرٌ فَنَظَرُوا فَإِذَا عَمْرُو بْنُ عَبَسَةَ فَأَرْسَلَ إِلَيْهِ مُعَاوِيَةُ فَسَأَلَهُ فَقَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏"‏مَنْ كَانَ بَيْنَهُ وَبَيْنَ قَوْمٍ عَهْدٌ فَلاَ يَشُدُّ عُقْدَةً وَلاَ يَحُلُّهَا حَتَّى يَنْقَضِيَ أَمَدُهَا أَوْ يَنْبِذَ إِلَيْهِمْ عَلَى سَوَاءٍ ‏"‏ ‏.‏ فَرَجَعَ مُعَاوِيَةُ

Narrated Amr ibn Abasah

There was a covenant between Mu'awiyah and the Byzantines, and he was marching toward their land. When the covenant expired, he attacked them. A man came riding a horse or a packhorse, saying, "Allah is the greatest! Allah is the greatest! Fulfillment, not treachery!" They looked and saw that it was 'Amr ibn 'Abasah. Mu'awiyah sent for him and asked him, and he said, "I heard the Messenger of Allah (ﷺ) saying: 'Whoever has a covenant with a people must not tighten a knot nor untie it until its term expires or he discards it to them on terms of equality.'" So Mu'awiyah returned.