"The Messenger of Allah ﷺ taught us the prayer. He stood up and said the takbir, and when he wanted to bow, he put his hands together and put his hands between his knees and bowed." News of that reached Sa'd and he said: "My brother has spoken the truth. We used to do that, then we were commanded to do this," meaning to hold the knees.  

عَلَّمَنَا رَسُولُ اللَّهِ ﷺ الصَّلاَةَ فَقَامَ فَكَبَّرَ فَلَمَّا أَرَادَ أَنْ يَرْكَعَ طَبَّقَ يَدَيْهِ بَيْنَ رُكْبَتَيْهِ وَرَكَعَ فَبَلَغَ ذَلِكَ سَعْدًا فَقَالَ صَدَقَ أَخِي قَدْ كُنَّا نَفْعَلُ هَذَا ثُمَّ أُمِرْنَا بِهَذَا يَعْنِي الإِمْسَاكَ بِالرُّكَبِ  

The Messenger of Allah ﷺ taught us how to pray. He then uttered the takbir (Allah is most great) and raised his hands; when he bowed, he joined his hands and placed them between his knees. When this (report) reached Sa'd, he said: My brother said truly. We used to do this; then we were later on commanded to do this, that is, to place the hands on the knees.  

عَبْدُ اللَّهِ عَلَّمَنَا رَسُولُ اللَّهِ ﷺ الصَّلاَةَ فَكَبَّرَ وَرَفَعَ يَدَيْهِ فَلَمَّا رَكَعَ طَبَّقَ يَدَيْهِ بَيْنَ رُكْبَتَيْهِ قَالَ فَبَلَغَ ذَلِكَ سَعْدًا فَقَالَ صَدَقَ أَخِي قَدْ كُنَّا نَفْعَلُ هَذَا ثُمَّ أُمِرْنَا بِهَذَا يَعْنِي الإِمْسَاكَ عَلَى الرُّكْبَتَيْنِ  

[Machine] The Messenger of Allah ﷺ taught us the prayer, so we said the Takbir (saying "Allahu Akbar") and raised our hands, then we performed the Ruku' (bowing) and placed our hands on our knees. We stayed in that position until Sa'd came and said, "My brother, you have spoken the truth, as we used to do this. Then we were commanded to do this." He took hold of his knees. 'Asim ibn Kulayb narrated this.  

عَلَّمَنَا رَسُولُ اللهِ ﷺ الصَّلَاةَ فَكَبَّرَ وَرَفَعَ يَدَيْهِ ثُمَّ رَكَعَ وَطَبَّقَ بَيْنَ يَدَيْهِ وَجَعَلَهُمَا بَيْنَ رُكْبَتَيْهِ فَبَلَغَ سَعْدًا فَقَالَ صَدَقَ أَخِي قَدْ كُنَّا نَفْعَلُ ذَلِكَ ثُمَّ أُمِرْنَا بِهَذَا وَأَخَذَ بِرُكْبَتَيْهِ حَدَّثَنِي عَاصِمُ بْنُ كُلَيْبٍ هَكَذَا  

"The Messenger of Allah ﷺ taught us the prayer. He stood up and said the takbir, and when he wanted to bow, he put his hands together and put his hands between his knees and bowed." News of that reached Sa'd and he said: "My brother has spoken the truth. We used to do that, then we were commanded to do this," meaning to hold the knees. (Using translation from Nasāʾī 1031)  

عَلَّمَنَا رَسُولُ اللهِ ﷺ الصَّلَاةَ فَقَامَ فَكَبَّرَ فَلَمَّا أَرَادَ أَنْ يَرْكَعَ طَبَّقَ يَدَيْهِ بَيْنَ رُكْبَتَيْهِ وَرَكَعَ فَبَلَغَ ذَلِكَ سَعْدًا فَقَالَ صَدَقَ أَخِي قَدْ كُنَّا نَفْعَلُ هَذَا ثُمَّ أُمِرْنَا بِهَذَا يَعْنِي الْإِمْسَاكَ بِالرُّكَبِ