'Abdullāh Ibn 'Abbās / Muḥammad al-Fīrūzabādī
تفسير : (so the twain journeyed on till, when they met a lad) between two townships, (he slew him) khidr killed him. ((moses) said: what! hast thou) o khidr (slain an innocent soul who hath slain no man? verily thou hast done a horrid thing) you have committed a horrendous, evil act.
Jalāl al-Dīn al-Maḥallī
تفسير : so they set off, after leaving the ship, making their way on foot, until, when they met a boy, who had not yet reached puberty, playing with [other] boys, among whom his face was the fairest — and he, al-khidr, slew him, by slitting his throat with a knife while he lay down, or by tearing his head off with his hand, or by smashing his head against a wall, all of which are [different] opinions (the coordinating fā’ [of fa-qatalahu, ‘and he slew him’] is used here because [it indicates that] the slaying took place after the encounter; the response to idhā, ‘when’ is [the following statement, qāla …]) — he, moses, said, to him: ‘have you slain an innocent soul, that is, a pure one that had not reached the age of [legal] responsibility (a variant reading [for zākiya] has zakiyya), [one slain] not in retaliation for another soul?, in other words, one that has not slain any soul. verily you have committed an dreadful thing’ (read nukran or nukuran), that is to say, an abomination.