Sahih Muslim 534
Sahih Muslim · Book 5: The Book of Mosques and Places of Prayer · The recommendation to place the hands on the knees when bowing, and the abrogation of tatbiq
'Alqama and Aswad reported that they went to 'Abdullah. He said:
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ عَبْدِ الرَّحْمَنِ الدَّارِمِيُّ ، أَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ مُوسَى ، عَنْ إِسْرَائِيلَ ، عَنْ مَنْصُورٍ ، عَنْ إِبْرَاهِيمَ ، عَنْ عَلْقَمَةَ ، وَالأَسْوَدِ ، أَنَّهُمَا دَخَلاَ عَلَى عَبْدِ اللَّهِ فَقَالَ أَصَلَّى مَنْ خَلْفَكُمْ قَالاَ نَعَمْ . فَقَامَ بَيْنَهُمَا وَجَعَلَ أَحَدَهُمَا عَنْ يَمِينِهِ وَالآخَرَ عَنْ شِمَالِهِ ثُمَّ رَكَعْنَا فَوَضَعْنَا أَيْدِيَنَا عَلَى رُكَبِنَا فَضَرَبَ أَيْدِيَنَا ثُمَّ طَبَّقَ بَيْنَ يَدَيْهِ ثُمَّ جَعَلَهُمَا بَيْنَ فَخِذَيْهِ فَلَمَّا صَلَّى قَالَ هَكَذَا فَعَلَ رَسُولُ اللَّهِ صلى الله عليه وسلم .
Have (people) behind you said prayer? They said: Yes. He stood between them ('Alqama and Aswad). One was on his right aide and the other was on his left. We then bowed and placed our hands on our knees. He struck our hands and then putting his hands together, palm to palm, placed them between his thighs. When he completed the prayer he said: This is how the Messenger of Allah (ﷺ) used to do.