Sunan an-Nasa'i 779
سنن النسائي#779Sahihأَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا أَبُو بَكْرِ بْنُ عَيَّاشٍ، عَنْ عَاصِمٍ، عَنْ زِرٍّ، عَنْ عَبْدِ اللَّهِ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لَعَلَّكُمْ سَتُدْرِكُونَ أَقْوَامًا يُصَلُّونَ الصَّلاَةَ لِغَيْرِ وَقْتِهَا فَإِنْ أَدْرَكْتُمُوهُمْ فَصَلُّوا الصَّلاَةَ لِوَقْتِهَا وَصَلُّوا مَعَهُمْ وَاجْعَلُوهَا سُبْحَةً " .
It was narrated that 'Abdullih said:"The Messenger of Allah (ﷺ) said: 'You may live to meet people who will be offering the prayer outside its (prayer) time. If you meet them, then offer the prayer on time, then pray with them and make that a voluntary prayer
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 10:3