What is required of the imam if he says the takbir and then remembers that he is in a state of ritual impurity?
Machine translationRead the Arabic original
The questioner:
He says: Honorable Shaykh, may Allah grant you success, if the imam says the takbir for the prayer and then remembers that he is in a state of ritual impurity, what does he do?
The Shaykh:
He leaves and tells them to wait, or otherwise one person takes his place to pray with them. Yes.
The questioner:
And is it permissible for him to appoint a substitute to complete the prayer?
The Shaykh:
Yes, he may appoint a substitute, he may appoint someone to pray with them. Yes.
The questioner:
He says: Does the ruling differ if he was in a state of wudu' but became ritually impure during the prayer?
The Shaykh:
If he was in a state of wudu' at the beginning of the prayer and his wudu' was broken, he may appoint a substitute to complete the prayer. Yes.
He says: Honorable Shaykh, may Allah grant you success, if the imam says the takbir for the prayer and then remembers that he is in a state of ritual impurity, what does he do?
The Shaykh:
He leaves and tells them to wait, or otherwise one person takes his place to pray with them. Yes.
The questioner:
And is it permissible for him to appoint a substitute to complete the prayer?
The Shaykh:
Yes, he may appoint a substitute, he may appoint someone to pray with them. Yes.
The questioner:
He says: Does the ruling differ if he was in a state of wudu' but became ritually impure during the prayer?
The Shaykh:
If he was in a state of wudu' at the beginning of the prayer and his wudu' was broken, he may appoint a substitute to complete the prayer. Yes.
Source
قناة «العلامة الدكتور صالح الفوزان»، [2263 -2802] ماذا يلزم الإمام إذا كبَّر؛ ثم تذكَّر أنه مُحدِث؟ - الشيخ صالح الفوزان — youtube.com
The Arabic text is a machine transcription of the audio recording.