Al-Harith ibn ‘Amr reported: The Messenger of Allah, peace and blessings be upon him, sent Mu’adh to Yemen and he said, “How will you judge?” Mu’adh said, “I will judge according to the Book of Allah.” The Prophet said, “What if it is not in the Book of Allah?” Mu’adh said, “Then, with the Sunnah of the messenger of Allah.” The Prophet said, “What if it is not in the Sunnah of the Messenger of Allah?” Mu’adh said, “Then, I will strive to form an opinion.” The Prophet said, “All praise is due to Allah, who has made suitable the messenger of the Messenger of Allah.”
Source: Sunan al-Tirmidhī 1327
Grade: Sahih (authentic) according to Ibn Abdul Barr
عَنْ الْحَارِثِ بْنِ عَمْرٍ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بَعَثَ مُعَاذًا إِلَى الْيَمَنِ فَقَالَ كَيْفَ تَقْضِي فَقَالَ أَقْضِي بِمَا فِي كِتَابِ اللَّهِ قَالَ فَإِنْ لَمْ يَكُنْ فِي كِتَابِ اللَّهِ قَالَ فَبِسُنَّةِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ فَإِنْ لَمْ يَكُنْ فِي سُنَّةِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ أَجْتَهِدُ رَأْيِي قَالَ الْحَمْدُ لِلَّهِ الَّذِي وَفَّقَ رَسُولَ رَسُولِ اللَّهِ
1327 سنن الترمذي كتاب الأحكام باب ما جاء في القاضي كيف يقضي
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