“Indeed,

Anas reported: Regarding the Surah, “Indeed, We have given you Al-Kauthar,” (108:1) the Prophet, peace be upon him, said, “It is a river in Paradise.” He said further, “I saw a river in Paradise whose banks had tents made of pearls. I asked: what are these, O Gabriel?” Gabriel said, “This is Al-Kauthar which Allah have given you.”

[Sunan At-Tirmidhi, Book 44, Number 3359, Sahih]

عَنْ أَنَسٍ  إِنَّا أَعْطَيْنَاكَ الْكَوْثَرَ  أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ هُوَ نَهْرٌ فِي الْجَنَّةِ قَالَ فَقَالَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ رَأَيْتُ نَهْرًا فِي الْجَنَّةِ حَافَّتَاهُ قِبَابُ اللُّؤْلُؤِ قُلْتُ مَا هَذَا يَا جِبْرِيلُ قَالَ هَذَا الْكَوْثَرُ الَّذِي أَعْطَاكَهُ اللَّهُ

قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ

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