What should one do who made a mistake in one of the obligatory parts of prayer out of forgetfulness, such as erring in the takbirat al-intiqal or the tahmid, and remembered their mistake just before prostrating?

If a worshipper makes a mistake in one of the obligatory parts of the prayer, and remembers before leaving the position of that obligation, he should perform it, and there is nothing upon him. However, if he has left the position of that obligation, he should continue his prayer and perform the prostration of forgetfulness (sujud al-sahw) before the salutation (taslim).

Scholars have differed on this matter. If he raises his head from bowing and remembers that he did not glorify Allah during his bowing, the relied-upon opinion in the Hanbali school is that he should return to perform the glorification before standing upright; otherwise, he should not return and should perform the prostration of forgetfulness.

Ibn Qudamah holds the view that he should not return to it, whether he remembered before or after standing upright, and should perform the prostration of forgetfulness. This is because the glorification has dropped with his raising, and the bowing is valid. If he were to return, he would be adding an unprescribed bowing.