10. Qadi ‘Iyad said: All scholars concur that if the urge reaches a level at which a person can no longer comprehend his prayer or observe its limits, it is impermissible for him to begin the prayer, and he must break it off should that condition overtake him while he is already praying.

11. Ibn al-Mulaqqin states in his Commentary on al-ʿUmda: In summary, resisting the call of the two impurities falls under four situations:

First: The urge is so overwhelming that he loses all awareness of the prayer. By unanimous agreement he may neither start the prayer nor remain in it.

Second: The case in which it is merely disliked—he performs the prayer but all inward humility has vanished. Its ruling is the same as that of someone who prays without khushūʿ; according to the authoritative position, the prayer remains valid.

Third: The urge leads him to omit a pillar or a condition. Here he is forbidden to enter the prayer, and if he does so the omission renders it invalid.

Fourth: The urge causes him to doubt whether he has fulfilled one of the pillars. Its ruling is identical to that of any doubt that arises for another reason: he proceeds on the basis of what is certain.