Sahih Muslim 2898 b
Mustaurid Qurashi reported:
I heard Allah's Messenger (ﷺ) as saying: The Last Hour would come when the Romans would form a majority amongst people. This reached 'Amr b. al-'As and he said: What are these ahadith which are being transmitted from you and which you claim to have heard from Allah's Messenger (ﷺ)? Mustaurid said to him: I stated only that which I heard from Allah's Messenger (ﷺ). Thereupon 'Amr said: If you state this (it is true), for they have the power of tolerance amongst people at the time of turmoil and restore themselves to sanity after trouble, and are good amongst people so far as the destitute and the weak are concerned.
حَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى التُّجِيبِيُّ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ وَهْبٍ، حَدَّثَنِي أَبُو شُرَيْحٍ،
 أَنَّ عَبْدَ الْكَرِيمِ بْنَ الْحَارِثِ، حَدَّثَهُ أَنَّ الْمُسْتَوْرِدَ الْقُرَشِيَّ قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله
 عليه وسلم يَقُولُ ‏
"‏ تَقُومُ السَّاعَةُ وَالرُّومُ أَكْثَرُ النَّاسِ ‏"‏ ‏.‏ قَالَ فَبَلَغَ ذَلِكَ عَمْرَو بْنَ الْعَاصِ
 فَقَالَ مَا هَذِهِ الأَحَادِيثُ الَّتِي تُذْكَرُ عَنْكَ أَنَّكَ تَقُولُهَا عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم
 فَقَالَ لَهُ الْمُسْتَوْرِدُ قُلْتُ الَّذِي سَمِعْتُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ فَقَالَ عَمْرٌو
 لَئِنْ قُلْتَ ذَلِكَ إِنَّهُمْ لأَحْلَمُ النَّاسِ عِنْدَ فِتْنَةٍ وَأَجْبَرُ النَّاسِ عِنْدَ مُصِيبَةٍ وَخَيْرُ النَّاسِ لِمَسَاكِينِهِمْ
 وَضُعَفَائِهِمْ ‏.‏