فَوَجَدَا عَبْدًا مِّنْ عِبَادِنَآ ءَاتَيْنَـٰهُ رَحْمَةً مِّنْ عِندِنَا وَعَلَّمْنَـٰهُ مِن لَّدُنَّا عِلْمًا
Fa wajadaa 'abdam min 'ibaadinaaa aatainaahu Rahmatam min 'indinaa wa 'allamnaahu mil ladunnaa 'ilmaa
There they found a servant from among our servants, one to whom we had granted mercy from ourselves and taught knowledge from our own presence.
This man is introduced by his relation to God alone, as a servant given mercy and taught knowledge. The name Khidr comes from hadith; the Qur'an never uses it here or anywhere. And min ladunnā, from our own presence, is the phrase later writers drew on for ʿilm ladunnī, knowledge that arrives rather than being acquired.