‘Bring them to me.’ The two men were trembling. He asked, ‘What prevented you from praying with us?’

They replied, ‘O Messenger of Allah, we had already prayed at our lodgings.’

He said, ‘Do not do that. If you pray at your lodgings and then come to a mosque where a congregation is praying, pray with them, for it will count as a voluntary prayer for you.’”

The second hadith is narrated by Salmān ibn Sālim, who said:

“I saw ʿAbd Allāh ibn ʿUmar sitting in the paved courtyard while the people were praying. I asked, ‘O ʿAbd Allāh, why are you not praying?’ He replied, ‘I have already prayed, and I heard the Messenger of Allah (may Allah bless him and grant him peace) say: “A prayer is not to be performed twice.”’”

How, then, can these two hadiths be reconciled?

He replied:

Praise be to Allah. The hadith of Ibn ʿUmar concerns repeating a prayer without any particular reason. There is no doubt that this is prohibited, and that it is disliked for a person deliberately to repeat a prayer without a reason warranting its repetition. For if a specified number were prescribed for a prayer established by Islamic law, a person could offer the noon prayer several times, the afternoon prayer several times, and so on. There is no doubt that such conduct is disliked.

As for the hadith of Ibn al-Aswad, it concerns repetition occasioned by a particular reason, as expressed in the Prophet’s words:

“If you pray at your lodgings and then come to a mosque where a congregation is praying, pray with them, for it will count as a voluntary prayer for you.”

The reason for repeating the prayer here is being present when the regular congregation prays. It is recommended for someone who has already prayed and then comes upon a regular congregation to pray with them.