Narrated Anas:

When the Prophet (ﷺ) was made to ascend to the Heavens, he said (after his return), "I came upon a river the banks of which were made of tents of hollow pearls. I asked Gabriel. What is this (river?) He replied, 'This is the Kauthar.'

حَدَّثَنَا آدَمُ، حَدَّثَنَا شَيْبَانُ، حَدَّثَنَا قَتَادَةُ، عَنْ أَنَسٍ ـ رضى الله عنه ـ قَالَ لَمَّا عُرِجَ بِالنَّبِيِّ صلى الله عليه وسلم إِلَى السَّمَاءِ قَالَ ‏

‏ أَتَيْتُ عَلَى نَهَرٍ حَافَتَاهُ قِبَابُ اللُّؤْلُؤِ مُجَوَّفًا فَقُلْتُ مَا هَذَا يَا جِبْرِيلُ قَالَ هَذَا الْكَوْثَرُ ‏

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