Sunan Abi Dawud, Hadith 4688 ⓘ
Ubayy b. Ka’b said : The boy whom al-Khidr had killed was created an infidel. Had he lived, he would have moved his parents to rebellion and unbelief.
حَدَّثَنَا الْقَعْنَبِيُّ، حَدَّثَنَا الْمُعْتَمِرُ، عَنْ أَبِيهِ، عَنْ رَقَبَةَ بْنِ مَصْقَلَةَ، عَنْ أَبِي إِسْحَاقَ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، عَنْ أُبَىِّ بْنِ كَعْبٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " الْغُلاَمُ الَّذِي قَتَلَهُ الْخَضِرُ طُبِعَ كَافِرًا وَلَوْ عَاشَ لأَرْهَقَ أَبَوَيْهِ طُغْيَانًا وَكُفْرًا " .
also referenced under: Hadith 4705 (DarusSalam)