If the imam stands up for the fifth rak'ah thinking it is the fourth, what is the ruling on his prayer and the prayer of the ma'mum?

The Shaykh : Please, and peace be upon you.

The questioner : An imam in prayer stood up and performed a fifth rak'ah thinking it was the fourth. What is the ruling on his prayer? He was reminded during the prayer and did not return. What is the ruling on his prayer and the ruling on the prayer of those who followed him?

The Shaykh : Did he prostrate after the two prostrations of forgetfulness?

The questioner: Yes.

The Shaykh : The prayer is valid. Your statement that he was reminded and did not respond to the reminder falls into one of two cases. The first is a state that I cannot imagine a Muslim persisting in, which is to be stubborn and arrogant in order to cover up the fact that he made a mistake in his prayer. If he did that, his prayer would be invalid because he would have added a rak'ah to the obligatory four-rak'ah prayer. However, since I asked you and you answered that he prostrated the two prostrations of forgetfulness, that is evidence that he was in a state of forgetfulness and that when he was reminded that this was the fifth rak'ah, he did not remember it at that moment, but rather remembered it afterwards and prostrated the two prostrations of forgetfulness. Therefore, his prayer is valid, and consequently, the prayer of those behind him is also valid.