Sunan Abi Dawud, Book 3, Hadith 1100 (USC-MSA)

Narrated Sahl ibn Sa'd: I never saw the Messenger of Allah raising his hands and praying on the pulpit or otherwise. But I saw him saying (doing) this way, and he would point with his forefinger making a circle by joining the middle finger with his thumb.

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا بِشْرٌ، - يَعْنِي ابْنَ الْمُفَضَّلِ - حَدَّثَنَا عَبْدُ الرَّحْمَنِ، - يَعْنِي ابْنَ إِسْحَاقَ - عَنْ عَبْدِ الرَّحْمَنِ بْنِ مُعَاوِيَةَ، عَنِ ابْنِ أَبِي ذُبَابٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، قَالَ مَا رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم شَاهِرًا يَدَيْهِ قَطُّ يَدْعُو عَلَى مِنْبَرِهِ وَلاَ عَلَى غَيْرِهِ وَلَكِنْ رَأَيْتُهُ يَقُولُ هَكَذَا وَأَشَارَ بِالسَّبَّابَةِ وَعَقَدَ الْوُسْطَى بِالإِبْهَامِ ‏.‏

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