It is a river granted to your Prophet ﷺ. Its banks are lined with hollow pearls, and its vessels are as numerous as the stars.
في قوله تعالى: {إنا أعطيناك الكوثر}.
هو نهر أعطيه نبيكم ﷺ، شاطئاه عليه در مجوف، آنيته كعدد النجوم.
Bukhari narrated it in tafsir (4965) from Khalid bin Yazid Kahili, who said, Israil narrated to us, from Abu Ishaq, from Abu Ubayda, who mentioned it.