Narrated Abu Huraira: The Prophet (ﷺ) said, "Al-Khadir was named so because he sat over a barren white land, it turned green with plantation after (his sitting over it)"
Book 60 · Hadith 75
صحيح البخاري
Narrated Abu Huraira: The Prophet (ﷺ) said, "Al-Khadir was named so because he sat over a barren white land, it turned green with plantation after (his sitting over it)"