Sahih al-Bukhari 651
Sahih al-Bukhari · Book 10: Call to Prayers (Adhaan) · Superiority of the Fajr (early morning) prayer in congregation.
Narrated Abu Musa:
حَدَّثَنَا مُحَمَّدُ بْنُ الْعَلاَءِ ، قَالَ حَدَّثَنَا أَبُو أُسَامَةَ ، عَنْ بُرَيْدِ بْنِ عَبْدِ اللَّهِ ، عَنْ أَبِي بُرْدَةَ ، عَنْ أَبِي مُوسَى ، قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم " أَعْظَمُ النَّاسِ أَجْرًا فِي الصَّلاَةِ أَبْعَدُهُمْ فَأَبْعَدُهُمْ مَمْشًى، وَالَّذِي يَنْتَظِرُ الصَّلاَةَ حَتَّى يُصَلِّيَهَا مَعَ الإِمَامِ أَعْظَمُ أَجْرًا مِنَ الَّذِي يُصَلِّي ثُمَّ يَنَامُ " .
The Prophet (ﷺ) said, "The people who get tremendous reward for the prayer are those who are farthest away (from the mosque) and then those who are next farthest and so on. Similarly one who waits to pray with the Imam has greater reward than one who prays and goes to bed. "