(6) باب الاِعْتِدَالِ فِي الرُّكُوعِ
It was narrated that Abu Humaid As-Sa'idi said:
"When the Prophet (ﷺ) bowed he was balanced, he did not make his head higher or lower than his back, and he put his hands on his knees."
Reference: Sunan an-Nasa'i 1039
In-book reference: Book 12, Hadith 11
English translation: Vol. 2, Book 12, Hadith 1040