(88) باب إِقَامَةِ الصُّلْبِ فِي الرُّكُوعِ
It was narrated that Abu Mas'ud said:
"The Messenger of Allah (ﷺ) said: 'The prayer is not valid if a man does not bring his backbone to rest while bowing and prostrating.'" (TH)
Reference (TH): Sunan an-Nasa'i 1027 (TH)
In-book reference (TH): Book 11, Hadith 152 (TH)
English translation (TH): Vol. 2, Book 11, Hadith 1028 (TH)