(150) باب صَلاَةِ مَنْ لاَ يُقِيمُ صُلْبَهُ فِي الرُّكُوعِ وَالسُّجُودِ
Narrated AbuMas'ud al-Badri:
The Prophet (ﷺ) said: A man's prayer does not avail him unless he keeps his back steady when bowing and prostrating. (FR)
Reference (FR): Sunan Abi Dawud 855 (FR)
In-book reference (FR): Book 2, Hadith 465 (FR)
English translation (FR): Book 3, Hadith 854 (FR)