Abdullah ibn Amr reported: The Messenger of Allah, peace and blessings be upon him, said, “When death approached Noah, upon him be peace, he called his sons and he said: Verily, my time is short and you must receive instruction. I command you with two and prohibit you with two. I forbid you from committing idolatry and arrogance. I command you to declare there is no God but Allah, for if the heavens and the earth and everything between them were placed on one side of the scale and the declaration of no God but Allah were placed on the other, it would surely outweigh it. Were the heavens and the earth a ring of solid iron and the declaration of no God but Allah were placed upon it, it would shatter it to pieces. I command you to declare the glory of Allah and His praises, for it is the prayer of all things and by it all things are given provision.”
Source: Musnad Aḥmad 7101
Grade: Sahih (authentic) according to Al-Arna’ut
عَنْ عَبْدِ اللهِ بْنِ عَمْرٍو قَالَ قَالَ رَسُولُ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ إِنَّ نُوحًا عَلَيْهِ السَّلَامُ لَمَّا حَضَرَتْهُ الْوَفَاةُ دَعَا ابْنَيْهِ فَقَالَ إِنِّي قَاصِرٌ عَلَيْكُمَا الْوَصِيَّةَ آمُرُكُمَا بِاثْنَتَيْنِ وَأَنْهَاكُمَا عَنِ اثْنَتَيْنِ أَنْهَاكُمَا عَنِ الشِّرْكِ وَالْكِبْرِ وَآمُرُكُمَا بِلَا إِلَهَ إِلَّا اللهُ فَإِنَّ السَّمَاوَاتِ وَالْأَرْضَ وَمَا فِيهِمَا لَوْ وُضِعَتْ فِي كِفَّةِ الْمِيزَانِ وَوُضِعَتْ لَا إِلَهَ إِلَّا اللهُ فِي الْكِفَّةِ الْأُخْرَى كَانَتْ أَرْجَحَ وَلَوْ أَنَّ السَّمَاوَاتِ وَالْأَرْضَ كَانَتَا حَلْقَةً فَوُضِعَتْ لَا إِلَهَ إِلَّا اللهُ عَلَيْهمَا لَفَصَمَتْهَا أَوْ لَقَصَمَتْهَا وَآمُرُكُمَا بِسُبْحَانَ اللهِ وَبِحَمْدِهِ فَإِنَّهَا صَلَاةُ كُلِّ شَيْءٍ وَبِهَا يُرْزَقُ كُلُّ شَيْءٍ
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