Al-Kahf 18:68

فَوَجَدَا عَبْدًا مِّنْ عِبَادِنَا آتَيْنَاهُ رَحْمَةً مِّنْ عِندِنَا وَعَلَّمْنَاهُ مِن لَّدُنَّا عِلْمًا

And they found a servant from among Our servants to whom we had given mercy from us and had taught him from Us a [certain] knowledge.

قَالَ لَهُ مُوسَىٰ هَلْ أَتَّبِعُكَ عَلَىٰ أَن تُعَلِّمَنِ مِمَّا عُلِّمْتَ رُشْدًا

Moses said to him, "May I follow you on [the condition] that you teach me from what you have been taught of sound judgement?"

قَالَ إِنَّكَ لَن تَسْتَطِيعَ مَعِيَ صَبْرًا

He said, "Indeed, with me you will never be able to have patience.

قَالَ سَتَجِدُنِي إِن شَاءَ اللَّهُ صَابِرًا وَلَا أَعْصِي لَكَ أَمْرًا

[Moses] said, "You will find me, if Allah wills, patient, and I will not disobey you in [any] order."

قَالَ فَإِنِ اتَّبَعْتَنِي فَلَا تَسْأَلْنِي عَن شَيْءٍ حَتَّىٰ أُحْدِثَ لَكَ مِنْهُ ذِكْرًا

He said, "Then if you follow me, do not ask me about anything until I make to you about it mention."

فَانطَلَقَا حَتَّىٰ إِذَا رَكِبَا فِي السَّفِينَةِ خَرَقَهَا ۖ قَالَ أَخَرَقْتَهَا لِتُغْرِقَ أَهْلَهَا لَقَدْ جِئْتَ شَيْئًا إِمْرًا

So they set out, until when they had embarked on the ship, al-Khidh r tore it open. [Moses] said, "Have you torn it open to drown its people? You have certainly done a grave thing."