كتاب فضائل الصحابة رضى الله تعالى عنهم
44
The Book of the Merits of the Companions
(52)
Chapter: The Virtues Of the Sahabah, Then Those Who Come After Them, Then Those Who Come After Them
(52)
باب فَضْلِ الصَّحَابَةِ ثُمَّ الَّذِينَ يَلُونَهُمْ ثُمَّ الَّذِينَ يَلُونَهُمْ ‏‏

'Abdullah (b. Mas'ud) reported Allah's Apostle (ﷺ) as saying:

The best among people are of my generation, then those next to them. (The narrator said): I do not know whether (he said) it three times or four times. Then there would fellow after them such persons whose evidence would precede the oath, and in case of some others, the oath (would precede) the evidence.
وَحَدَّثَنِي الْحَسَنُ بْنُ عَلِيٍّ الْحُلْوَانِيُّ، حَدَّثَنَا أَزْهَرُ بْنُ سَعْدٍ السَّمَّانُ، عَنِ ابْنِ عَوْنٍ، عَنْ إِبْرَاهِيمَ، عَنْ عَبِيدَةَ، عَنْ عَبْدِ اللَّهِ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏"‏ خَيْرُ النَّاسِ قَرْنِي ثُمَّ الَّذِينَ يَلُونَهُمْ ثُمَّ الَّذِينَ يَلُونَهُمْ ‏"‏ ‏.‏ فَلاَ أَدْرِي فِي الثَّالِثَةِ أَوْ فِي الرَّابِعَةِ قَالَ ‏"‏ ثُمَّ يَتَخَلَّفُ مِنْ بَعْدِهِمْ خَلْفٌ تَسْبِقُ شَهَادَةُ أَحَدِهِمْ يَمِينَهُ وَيَمِينُهُ شَهَادَتَهُ ‏"‏ ‏.‏
Reference : Sahih Muslim 2533 d
In-book reference : Book 44, Hadith 301
USC-MSA web (English) reference : Book 31, Hadith 6153
  (deprecated numbering scheme)