Chapter: To prostrate on seven bones
Narrated Ibn `Abbas:The Prophet (ﷺ) was ordered (by Allah) to prostrate on seven parts and not to tuck up the clothes or hair (while praying). Those parts are: the forehead (along with the tip of nose), both hands, both knees, and (toes of) both feet.
Reference
Sahih al-Bukhari 809
In-book reference
Book 10, Hadith 204
USC-MSA web (English)
Vol. 1, Book 12, Hadith 773
Translation by Dr. M. Muhsin Khan · Language: EN
Sahih
Arabic Text
حَدَّثَنَا قَبِيصَةُ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، أُمِرَ النَّبِيُّ صلى الله عليه وسلم أَنْ يَسْجُدَ عَلَى سَبْعَةِ أَعْضَاءٍ، وَلاَ يَكُفَّ شَعَرًا وَلاَ ثَوْبًا الْجَبْهَةِ وَالْيَدَيْنِ وَالرُّكْبَتَيْنِ وَالرِّجْلَيْنِ.