18.80
Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
(And as for the lad) whom I killed, (his parents were believers) and of the greatest people of that township (and We feared lest he should oppress them) and your Lord Knew that he will overburden them (by rebellion and disbelief) by means of his rebellion and disobedience, and by lying in oath and so He killed him.
And as for the boy his parents were believers and We feared lest he should overwhelm them with insolence and disbelief — for he is as described by the hadīth of Muslim ‘He was incorrigibly disposed to disbelief and had he lived longer this disposition of his would have oppressed them because of their love for him they would have followed him in such a path of disbelief’.
And as for the boy, his parents, who were the spirit and physical nature, were believers, affirmers of the Oneness by virtue of their yielding as they wayfare in obedience of God, submit to God's command and comply with what God desires from them; and We feared lest he should overwhelm them, totally cover them, with insolence, towards them by manifesting himself in his I-ness at the presential vision of the spirit, and ingratitude, towards the grace of having them by his disobedience and evil action; or with ingratitude for the veil so that he ends up spoiling for them their affair and their religion and invalidating [for them] their servanthood of God.
(his parents were believers, and we feared he would oppress them by rebellion and disbelief) Their love for him might make them follow him in disbelief. Qatadah said, "His parents rejoiced when he was born and grieved for him when he was killed. If he had stayed alive, he would have been the cause of their doom. So let a man be content with the decree of Allah, for the decree of Allah for the believer, if he dislikes it, is better for him than if He were to decree something that he likes for him.'' An authentic Hadith says;
(So we intended that their Lord should exchange him for them for one better in righteousness and nearer to mercy. ) A child who was better than this one, a child for whom they would feel more compassion. This was the view of Ibn Jurayj.
18.77-82
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
In connection with this story, a very hard problem arises to which an answer must be found: Two of the three things done by Hadrat Khidr are obviously against those commandments of the Law which have always been in force since the creation of man. No law allows anyone the right to damage the property of another and kill an innocent person. So much so that if a man were to know by inspiration that some usurper would illegally seize a certain boat, and that a certain boy would be involved in a rebellion and unbelief, even then no law, sent down by Allah, makes it lawful that one should bore a hole in the boat and kill the innocent boy by virtue of one's inspiration. If in answer to this, one were to say that Hadrat Khidr committed these two acts by the Commands of Allah, this does not solve the problem, for the question is not this, "By whose command did Hadrat Khidr commit these acts"? but it is this: "What was the nature of these commands"? This is important because Hadrat Khidr did these acts in accordance with Divine Command, for he himself says that these acts of his were not done by his own authority, but were moved by the mercy of Allah, and Allah Himself has testified this by saying: "We gave him a special knowledge from Ourselves". Thus it is beyond any doubt that these acts were done by the Command of Allah, but the question about the nature of the command remains there, for it is obvious that these commands were not legal because it is not allowed by any Divine Law, and the fundamental principles of the Qur'an also do not allow that a person should kill another person without any proof of his guilt. Therefore we shall have to admit that these commands belonged to one of those decrees of Allah in accordance with which one sick person recovers, while another dies: one becomes prosperous and the other is ruined. If the Commands given to Hadrat Khidr were of this nature, then one must come to the conclusion that Hadrat Khidr was an angel (or some other kind of Allah's creation) who is not bound by the Divine Law prescribed for human beings, for such commands as have no legal aspect, can be addressed to angels only. This is because the question of the lawful or the unlawful cannot arise about them: they obey the Commands of Allah without having any personal power. In contrast to them, a man shall be guilty of a sin whether he does any such thing inadvertently by intuition or by some inspiration, if his act goes against some Divine Commandment. This is because a man is bound to abide by Divine Commandments as a man, and there is no room whatsoever in the Divine Law that an act may become lawful for a man merely because he had received an instruction by inspiration and had been informed in a secret way of the wisdom of that unlawful act. The above-mentioned principle has been unanimously accepted by scholars of the Divine Law and the leaders of Sufism. `Allamah Alusi has cited in detail the sayings of 'Abdul Wahhab Shi`irani, Muhy-ud-Din ibn-`Arabi, Mujaddid Alf Thani, Shaikh 'Abdul-Qadir Jilani, Junaid Baghdadi, Sirri Saqti, Abul-Hussain An-nuri, Abu Said-al-Kharraz, Ahmad ud-Dainauri and Imam Ghazzali to this effect that it is not lawful even for a sufi to act in accordance with that inspiration of his own which goes against a fundamental of law. (Ruh-ul-Ma ani, Vol. XVI, pp. 16-18). That is why we have come to the conclusion that Hadrat Khidr must be an angel, or some other kind of Allah's creation, exempted from human law, for he could not be the only exception to the above-mentioned formula. Therefore we inevitably come to the conclusion that he was one of those Servants of Allah who act in accordance with the will of Allah and not in accordance with the Divine Law prescribed for human beings. We would have accepted the theory that Hadrat Khidr was a human being, if the Qur'an had plainly asserted that the "servant" to whom Prophet Moses was sent for training, was a man, but the Qur'an does not specifically say that he was a human being but says that he was "one of Our Servants" which does not show that he was necessarily a human being. Besides this, there is no Tradition which specifically says that Hadrat Khidr was a human being. In the authentic traditions related by Said bin Jubair, Ibn `Abbas, Ubayy bin Ka`ab from the Holy Prophet, the Arabic word,,}i~ (rajul) has been used for Hadrat Khidr, which though generally used for human beings, is not exclusively used for human beings. In the Holy Qur'an itself, this word has been used for Jinns also (LXXIII 6). It is also obvious that when a jinn or an angel or an invisible being will come before a human being, he will surely come in human shape and, in that form; he will be called a bashar (man), just like the angel who came before Mary in the shape of a human being (XIX: 17). Thus the word rajul, used for Hadrat Khidr in the above mentioned Tradition by the Holy Prophet, does not necessarily mean that he was a human being. Therefore we are quite justified in the light of the above discussion to believe that Hadrat Khidr was one of the angels or some other kind of Allah's creation who is not bound by the Divine Law prescribed for human beings. Some of the former scholars of the Qur'an have also expressed the same opinion which. has been cited by lbn Kathir in his Commentary on the authority of Mawardi.