The Ruling on One Who prays and forgets the Iqamah or Al-Fatihah
Question :
A man performed the 'Asr prayer and he forgot the Iqamah; what is incumbent upon him? Should he repeat the Rak'ah if he forgets Al-Fatihah, or is the prayer complete?
Answer:
Leaving the Iqamah does no harm, because it is not a condition for the acceptance of prayer, nor is it one of its obligations. It was only prescribed in order to call the people to stand up in prayer. However, it should not be deliberately missed.
As for not reciting Al-Fatihah due to forgetfulness, if he is the Imam, he must repeat the Rak'ah in which he did not recite it, and likewise, if he is praying alone. As for the one who is led in prayer, the Imam bears the responsibility for it if he forgets it. But as for the Imam deliberately not reciting it, the prayer will be invalid and the whole prayer must be repeated; as for the one behind the Imam, the most apparent view is that he does not have to repeat the prayer, instead the Imam bears the responsibility. And Allah knows best.
Source:
Ibn Jibreen
Fatawa Islamiyah, Vol. 2 Page 210
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