صَحِيحُ مُسْلِمٍ
Sahih Muslim 495 a
The Book of Prayers
The Description Of The Prayer, With What It Begins And Ends. The Description Of Bowing And Moderation Therein, And Of Prostration And Moderation Therein. Tashah-hud After Each Two Rak'ah Of Four Rak'ah Prayers. Description Ol Sitting Between The Two Prostrations, And In The First Tashah-hud
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا بَكْرٌ، - وَهُوَ ابْنُ مُضَرَ - عَنْ جَعْفَرِ بْنِ رَبِيعَةَ، عَنِ الأَعْرَجِ، عَنْ عَبْدِ اللَّهِ بْنِ مَالِكٍ ابْنِ بُحَيْنَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ إِذَا صَلَّى فَرَّجَ بَيْنَ يَدَيْهِ حَتَّى يَبْدُوَ بَيَاضُ إِبْطَيْهِ .
'Abdullah b. Malik ibn Bujainah reported: When the Prophet (ﷺ) prostrated, lie spread out his arms so that the whiteness of his armpits was visible.
Sahih Muslim, 495 aSahihصحيح