Wābisah (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) saw a man praying alone behind the row, so he commanded him to repeat his prayer.
Original Arabic
عَنْ وَابِصَةَ رضي الله عنه: أَنَّ رَسُولَ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ رَأَى رَجُلًا صَلَّى وَحْدَهُ خَلْفَ الصَّفِّ، فَأَمَرَهُ أَنْ يُعِيدَ صَلَاتَهُ.
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