Sahih (Sahih Muslim)
حَدَّثَنَا هَارُونُ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا عَفَّانُ بْنُ مُسْلِمٍ، حَدَّثَنَا هَمَّامٌ، حَدَّثَنَا قَتَادَةُ، عَنْ أَنَسٍ، قَالَ مَرَّ غُلاَمٌ لِلْمُغِيرَةِ بْنِ شُعْبَةَ وَكَانَ مِنْ أَقْرَانِي فَقَالَ النَّبِيُّ صلى الله عليه وسلم " إِنْ يُؤَخَّرْ هَذَا فَلَنْ يُدْرِكَهُ الْهَرَمُ حَتَّى تَقُومَ السَّاعَةُ " .
Anas reported:A young boy of Mughira b. Shu'ba happened to pass by (the Holy Prophet) and he was of my age. Thereupon Allah's Apostle (ﷺ) said: If he lives long he would not grow very old till the Last Hour would come (to the old people of this generation)