Sahih al-Bukhari, Book 81, Hadith 143 (In-Book) ⓘ
Narrated Sahl bin Sa`d: Allah's Messenger said, "Seventy thousand or seven hundred thousand of my followers will enter Paradise. (Abu Hazim, the sub-narrator, is not sure as to which of the two numbers is correct.) They will be holding on to each other, the first will not entering the last one does, their faces like the moon on a full moon night."
حَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا عَبْدُ الْعَزِيزِ، عَنْ أَبِي حَازِمٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لَيَدْخُلَنَّ الْجَنَّةَ مِنْ أُمَّتِي سَبْعُونَ أَوْ سَبْعُمِائَةِ أَلْفٍ ـ لاَ يَدْرِي أَبُو حَازِمٍ أَيُّهُمَا قَالَ ـ مُتَمَاسِكُونَ، آخِذٌ بَعْضُهُمْ بَعْضًا، لاَ يَدْخُلُ أَوَّلُهُمْ حَتَّى يَدْخُلَ آخِرُهُمْ، وُجُوهُهُمْ عَلَى صُورَةِ الْقَمَرِ لَيْلَةَ الْبَدْرِ " .
also referenced under: Hadith 6554 (DarusSalam) & Volume 8, Book 76, Hadith 560 (USC-MSA)