Does raising the foot during prostration invalidate the prayer or render it unacceptable without a valid excuse?

The scholars have agreed that prostration (sujud) must be performed on seven limbs: the face, the hands, the knees, and the tips of the feet, based on the Prophet's (peace be upon him) saying: "I have been commanded to prostrate on seven bones: on the forehead, the hands, the knees, and the tips of the feet."

They differed regarding one who prostrates on their face but omits prostrating on one of these limbs: does their prayer become invalid or not? Some held the view that it does not become invalid because the term "sujud" (prostration) only refers to the face. Others held the view that it becomes invalid if one does not prostrate on all seven limbs, due to the authentic hadith.

Among those who held the first view are Imam Abu Hanifa, Malik, and Al-Shafi'i (in one narration). Among those who held the view of invalidity are Imam Ahmad and Al-Shafi'i (in the more correct view).

Therefore, it is incumbent to advise and guide those who pray with their foot raised during prostration without an excuse, and to alert them to the possibility of their prayer being ruled invalid.