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Surah 11. Hud
Ayah 45 - 47
45 وَنَادَىٰ نُوحٌ رَّبَّهُۥ فَقَالَ رَبِّ إِنَّ ٱبْنِى مِنْ أَهْلِى وَإِنَّ وَعْدَكَ ٱلْحَقُّ وَأَنتَ أَحْكَمُ ٱلْحَـٰكِمِينَ
46 قَالَ يَـٰنُوحُ إِنَّهُۥ لَيْسَ مِنْ أَهْلِكَ ۖ إِنَّهُۥ عَمَلٌ غَيْرُ صَـٰلِحٍ ۖ فَلَا تَسْـَٔلْنِ مَا لَيْسَ لَكَ بِهِۦ عِلْمٌ ۖ إِنِّىٓ أَعِظُكَ أَن تَكُونَ مِنَ ٱلْجَـٰهِلِينَ
47 قَالَ رَبِّ إِنِّىٓ أَعُوذُ بِكَ أَنْ أَسْـَٔلَكَ مَا لَيْسَ لِى بِهِۦ عِلْمٌ ۖ وَإِلَّا تَغْفِرْ لِى وَتَرْحَمْنِىٓ أَكُن مِّنَ ٱلْخَـٰسِرِينَ
45. And Nuh called upon his Lord and said, "O my Lord! Verily, my son is of my family! And certainly, Your promise is true, and You are the Most Just of the judges.'' 46. He said: "O Nuh! Surely, he is not of your family; verily, his work is unrighteous, so ask not of Me that of which you have no knowledge! I admonish you, lest you should be one of the ignorant.'' 47. Nuh said: "O my Lord! I seek refuge with You from asking You that of which I have no knowledge. And unless You forgive me and have mercy on me, I would indeed be one of the losers.''
This was a request for information and an inquiry from Nuh concerning the cirumstances of his son's drowning.
(and said, "O my Lord! Verily, my son is of my family!'') This means, "Verily, You promised to save my family and Your promise is the truth that does not fail. Therefore, how can he (my son) be drowned and You are the Most Just of the judges''
(He (Allah) said: "O Nuh! Surely, he is not of your family...'') This means, "He (your son) is not of those whom I promised to save. I only promised you that I would save those of your family who believe.'' For this reason Allah said,
l(and your family except him against whom the Word has already gone forth.) ﴿11:40﴾ Thus, for his son, it had already been decreed that he would be drowned due to his disbelief and his opposition to his father, the Prophet of Allah, Nuh peace be upon him. Concerning Allah's statement,
(Surely, he is not of your family;) meaning that he (Nuh's son) was not among those whom Allah promised to save. `Abdur-Razzaq recorded that Ibn `Abbas said, "He was the son of Nuh, but he opposed him in deeds and intention.'' `Ikrimah said in some of the modes of recitation it said here, (إِنَّهُ عَمِلَ عَمَلًا غَيْرَ صَالِحٍ) "Verily, he (Nuh's son) worked deeds that were not righteous.''