Jami` at-Tirmidhi 367
جامع الترمذي#367Sahihحَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا اللَّيْثُ بْنُ سَعْدٍ، عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ بْنِ الأَشَجِّ، عَنْ نَابِلٍ، صَاحِبِ الْعَبَاءِ عَنِ ابْنِ عُمَرَ، عَنْ صُهَيْبٍ، قَالَ مَرَرْتُ بِرَسُولِ اللَّهِ صلى الله عليه وسلم وَهُوَ يُصَلِّي فَسَلَّمْتُ عَلَيْهِ فَرَدَّ إِلَىَّ إِشَارَةً . وَقَالَ لاَ أَعْلَمُ إِلاَّ أَنَّهُ قَالَ إِشَارَةً بِإِصْبَعِهِ . قَالَ وَفِي الْبَابِ عَنْ بِلاَلٍ وَأَبِي هُرَيْرَةَ وَأَنَسٍ وَعَائِشَةَ .
Suhaib narrated:"I passed by Allah's Messenger (S) while he was performing Salat, so I said greeted him with Salam, and he returned it by making signals." He said: "I do not know except that he said: 'He indicated with his finger
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: 2:219