"Al-Bara' described the prostration to us. He places his hands on the ground and raised his posterior and said: 'This is what I saw the Messenger of Allah ﷺ doing." (Using translation from Nasāʾī 1104)  

وَصَفَ لَنَا الْبَرَاءُ السُّجُودَ فَوَضَعَ يَدَيْهِ بِالْأَرْضِ وَرَفَعَ عَجِيزَتَهُ وَقَالَ «هَكَذَا رَأَيْتُ النَّبِيَّ ﷺ يَفْعَلُ»  

When the Messenger of Allah ﷺ prayed he would Jakhkha. (Using translation from Nasāʾī 1105)  

أَنَّ رَسُولَ اللهِ ﷺ كَانَ إِذَا صَلَّى جَخَّ  

When the Prophet ﷺ prostrated, lie spread out his arms so that the whiteness of his armpits was visible. (Using translation from Muslim 495a)  

أَنَّ رَسُولَ اللهِ ﷺ كَانَ إِذَا صَلَّى فَرَّجَ بَيْنَ يَدَيْهِ حَتَّى يَبْدُو بَيَاضَ إِبِطَيْهِ  

"If I were in front of the Messenger of Allah ﷺ I would be able to see the whiteness of his armpits." (One of the narrators) Abu Mijlaz said: "It is as if he said that because he was praying." (Using translation from Nasāʾī 1107)  

«لَوْ كُنْتَ بَيْنَ يَدَيْ رَسُولِ اللهِ ﷺ لَأَبْصَرْتَ إِبِطَهُ» قَالَ أَبُو مِجْلَزٍ «كَأَنَّهُ قَالَ ذَلِكَ لِأَنَّهُ فِي صَلَاةٍ»  

"I prayed with the Messenger of Allah ﷺ and I used to see the whiteness of his armpits when he prostrated." (Using translation from Nasāʾī 1108)  

«صَلَّيْتُ مَعَ رَسُولِ اللهِ ﷺ فَكُنْتُ أَرَى عُفْرَةَ إِبِطِهِ إِذَا سَجَدَ»