[Machine] In His saying, exalted be He, "{Alif-Lam-Mim. The Romans have been defeated}" [Surah Ar-Rum, verse 2], it is said that the Romans were defeated and that they also defeated [their opponents]. The pagans desired that the Persians would prevail over the Romans, while the Muslims desired that the Romans would prevail over the Persians because they were ahl al-kitab (People of the Book). They mentioned this to Abu Bakr, and Abu Bakr mentioned it to the Messenger of Allah ﷺ . The Messenger of Allah ﷺ said, "They will definitely prevail." Abu Bakr relayed this to them. They said, "Let there be a contract between us and you. If we prevail, we will have such and such, and if you prevail, you will have such and such." So, they agreed to a duration of five years.  

فِي قَوْلِهِ تَعَالَى {§الم غُلِبَتِ الرُّومُ} [الروم 2] قَالَ غَلَبَتْ وَغُلِبَتْ كَانَ الْمُشْرِكُونَ يُحِبُّونَ أَنْ تَظْهَرَ فَارِسُ عَلَى الرُّومِ وَكَانَ الْمُسْلِمُونَ يُحِبُّونَ أَنْ تَظْهَرَ الرُّومُ عَلَى فَارِسَ لِأَنَّهُمْ أَهْلُ كِتَابٍ فَذَكَرُوا لِأَبِي بَكْرٍ فَذَكَرَ أَبُو بَكْرٍ لِرَسُولِ اللهِ ﷺ فَقَالَ رَسُولُ اللهِ ﷺ «أَمَا إِنَّهُمْ سَيَغْلِبُونَ» فَذَكَرَهُ أَبُو بَكْرٍ ؓ فَقَالُوا اجْعَلْ بَيْنَنَا وَبَيْنَكَ أَجَلًا فَإِنْ ظَهَرْنَا كَانَ لَنَا كَذَا وَكَذَا وَإِنْ ظَهَرْتُمْ كَانَ لَكُمْ كَذَا وَكَذَا فَجَعَلَ أَجْلَ خَمْسِ سِنِينَ