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bayhaqi:20312 – Abū Naṣr b. Qatādah al-Anṣārī And ʾAbū Ḥāzim al-Ḥāfiẓ > Abū al-Faḍl b. Khamīrūwayh > Aḥmad b. Najdah > Saʿīd b. Manṣūr > Hushaym > Sayyār > al-Shaʿbī > Lammā Baʿath ʿUmar b. al-Khaṭṭāb Shurayḥ > Qaḍāʾ al-Kūfah

[Machine] Look at what is clear to you in the book of Allah, so do not ask anyone about it. And whatever is not clear to you in the book of Allah, follow the Sunnah in it. And whatever is not clear to you in the Sunnah, then strive in your opinion regarding it.  

البيهقي:٢٠٣١٢ – أَخْبَرَنَا أَبُو نَصْرِ بْنُ قَتَادَةَ الْأَنْصَارِيُّ وَأَبُو حَازِمٍ الْحَافِظُ قَالَا ثنا أَبُو الْفَضْلِ بْنُ خَمِيرُوَيْهِ أنبأ أَحْمَدُ بْنُ نَجْدَةَ ثنا سَعِيدُ بْنُ مَنْصُورٍ ثنا هُشَيْمٌ ثنا سَيَّارٌ عَنِ الشَّعْبِيِّ قَالَ لَمَّا بَعَثَ عُمَرُ بْنُ الْخَطَّابِ ؓ شُرَيْحًا عَلَى قَضَاءِ الْكُوفَةِ قَالَ

انْظُرْ مَا تَبَيَّنَ لَكَ فِي كِتَابِ اللهِ فَلَا تَسْأَلْنَ عَنْهُ أَحَدًا وَمَا لَمْ يَتَبَيَّنْ لَكَ فِي كِتَابِ اللهِ فَاتَّبِعْ فِيهِ السُّنَّةَ وَمَا لَمْ يَتَبَيَّنْ لَكَ فِي السُّنَّةِ فَاجْتَهَدْ فِيهِ رَأْيَكَ  

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Collected by Suyūṭī
suyuti:2-3575b – al-Shaʿbi > Lammā Baʿath ʿUmar Shurayḥ > Qaḍāʾ al-Kūfah
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السيوطي:٢-٣٥٧٥b –

"عَنِ الشَّعْبِىِّ قَالَ: لَمَّا بَعَثَ عُمَرُ شُرَيْحًا عَلَى قَضَاءِ الْكُوفَةِ قَاَل: (انظر) مَا تَبَيَّن لَكَ في كِتَابِ اللهِ فَلاَ تَسْأَلْ عَنْهُ أَحَدًا، وَمَا لَمْ يَتَبَيَّنْ لَكَ في كِتَابِ اللهِ فَاتَّبِعْ فِيهِ السُّنَّةَ، وَمَا لَمْ يَتَبَيَّنْ لَكَ في السُّنَّةِ فَاجْتَهِدْ فِيهِ رَأيَكَ".  

[ص] سعيد بن منصور [ق] البيهقى في السنن