Q 28:14

And when he reached maturity, and was complete, We bestowed on him Hukm and knowledge. And thus do We reward the doers of good (14)And he entered the city when its people were unaware: and he found there two men fighting, – one of his party, and the other of his foes. The man of his (own) party asked him for help against his foe, so Musa struck him with his fist and he died. He said: "This is of Shaytan's doing, verily, he is a plain misleading enemy. (15)He said: "My Lord! Verily, I have wronged myself, so forgive me." Then He forgave him. Verily, He is the Oft-Forgiving, the Most Merciful (16)He said: "My Lord! For that with which You have favored me, I will nevermore be a helper of the criminals! (17) How Musa killed a Coptic Man Having described Musa's beginnings, Allah then tells us that when he reached maturity, and was complete in stature, Allah gave him Hukm and religious knowledge. Mujahid said that this means prophethood. وَكَذَٰلِكَ نَجْزِي الْمُحْسِنِينَ (And thus do We reward the doers of good.) Then Allah describes how Musa reached the status that was decreed for him, that of Prophethood and speaking to Allah, as a direct consequence of killing the Coptic, which was the reason why he left Egypt and went to Madyan. Allah says: وَدَخَلَ الْمَدِينَةَ عَلَىٰ حِينِ غَفْلَةٍ مِنْ أَهْلِهَا (And he entered the city when its people were unaware.) Ibn Jurayj narrated from 'Ata' Al-Khurasani, from Ibn 'Abbas, "That was between Maghrib and 'Isha'." Ibn Al-Munkadir narrated from 'Ata' bin Yasar from Ibn 'Abbas, "That was in the middle of the day." This was also the view of Sa'id bin Jubayr, 'Ikrimah, As-Suddi and Qatadah. فَوَجَدَ فِيهَا رَجُلَيْنِ يَقْتَتِلَانِ (and he found there two men fighting,) meaning, hitting one another and struggling with one another. هَٰذَا مِنْ شِيعَتِهِ (one of his party,) meaning, an Israelite, وَهَٰذَا مِنْ عَدُوِّهِ (and the other of his foes.) meaning, a Coptic. This was the view of Ibn 'Abbas, Qatadah, As-Suddi and Muhammad bin Ishaq. The Israelite man asked Musa, peace be upon him, for help, and Musa took advantage of the fact that people were not paying attention, so he went to the Coptic man and فَوَكَزَهُ مُوسَىٰ فَقَضَىٰ عَلَيْهِ (so Musa struck him with his fist and he died.) Mujahid said, "This means he punched him with his fist." And then he died. قَالَ (He said) refers to Musa. هَٰذَا مِنْ عَمَلِ الشَّيْطَانِ ۖ إِنَّهُ عَدُوٌّ مُضِلٌّ مُبِينٌ - قَالَ رَبِّ إِنِّي ظَلَمْتُ نَفْسِي فَاغْفِرْ لِي فَغَفَرَ لَهُ ۚ إِنَّهُ هُوَ الْغَفُورُ الرَّحِيمُ - قَالَ رَبِّ بِمَا أَنْعَمْتَ عَلَيَّ ("This is of Shaytan's doing, verily, he is a plain misleading enemy." He said: "My Lord! Verily, I have wronged myself, so forgive me." Then He forgave him. Verily, He is the Oft-Forgiving, the Most Merciful. He said: "My Lord! For that with which You have favored me,) meaning, 'what You have given me of prestige, power and blessings – ' فَلَنْ أَكُونَ ظَهِيرًا (I will nevermore be a helper of the criminals!) 'those who disbelieve in You and go against Your commands.'