and places his face firmly on the ground until his joints become still and relaxed. Then he says, ‘Allah is the Greatest,’ sits upright on his buttocks, and straightens his spine.”

He thus explained that straightening the spine occurs when rising from prostration, not while lowering oneself. The two preceding hadiths establish the obligation both to return upright in these two positions and to remain still. However, concerning bowing, prostration, and sitting, he said:

“Until you are still while bowing, until you are still while prostrating, and until you are still while sitting.”

Concerning rising from bowing, he said:

“Until you stand upright, and until you stand erect.”

This is because a person standing becomes upright and erect, which necessarily entails stillness. By contrast, someone bowing or prostrating is not erect. Nor can someone sitting be described as completely upright and straight: he may lean to one side, particularly in the tawarruk sitting posture, or forwards, because the limbs on which he sits are bent rather than straight and upright.

Nevertheless, Ibn Mājah narrated that he—may Allah bless him and grant him peace—said concerning rising from bowing:

“Until you are still while standing.”

ʿAlī ibn Shaybān al-Hanafī reported:

“We set out and came to the Messenger of Allah—may Allah bless him and grant him peace. We pledged allegiance to him and prayed behind him. Out of the corner of his eye, he caught sight of a man who was not performing his prayer properly—meaning that he was not straightening his spine in bowing and prostration. When the Prophet—may Allah bless him and grant him peace—had finished the prayer, he said: ‘O Muslims, there is no valid prayer