"The people asked 'Abdullah too many questions one day, and 'Abdullah said: 'There was a time when we did not pass so many judgments, but now that time is over. Now Allah, the Mighty and Sublime, has decreed that we reach a time when, as you see, (we are asked to pass many judgments). Whoever among you is asked to pass a judgment after this day, let him pass judgment according to what is in the Book of Allah. If he is faced with a matter that is not mentioned in the Book of Allah, let him pass judgment according to the way His Prophet [SAW] passed judgment. If he is faced with a matter that is not mentioned in the Book of Allah and concerning which His Prophet did not pass judgment, then let him pass judgment according to the way the righteous passed judgment. If he is faced with a matter that is not mentioned in the Book of Allah, and concerning which His Prophet and the righteous did not pass judgment, then let him strive to work it out, and let him not say 'I am afraid, I am afraid.' For that which is lawful is clear and that which is unlawful is clear, and between them are matters which are not as clear. Leave that which makes you doubt for that which does not make you doubt.'"  

أَكْثَرُوا عَلَى عَبْدِ اللَّهِ ذَاتَ يَوْمٍ فَقَالَ عَبْدُ اللَّهِ إِنَّهُ قَدْ أَتَى عَلَيْنَا زَمَانٌ وَلَسْنَا نَقْضِي وَلَسْنَا هُنَالِكَ ثُمَّ إِنَّ اللَّهَ ﷻ قَدَّرَ عَلَيْنَا أَنْ بَلَغْنَا مَا تَرَوْنَ فَمَنْ عَرَضَ لَهُ مِنْكُمْ قَضَاءٌ بَعْدَ الْيَوْمِ فَلْيَقْضِ بِمَا فِي كِتَابِ اللَّهِ فَإِنْ جَاءَ أَمْرٌ لَيْسَ فِي كِتَابِ اللَّهِ فَلْيَقْضِ بِمَا قَضَى بِهِ نَبِيُّهُ ﷺ فَإِنْ جَاءَ أَمْرٌ لَيْسَ فِي كِتَابِ اللَّهِ وَلاَ قَضَى بِهِ نَبِيُّهُ ﷺ فَلْيَقْضِ بِمَا قَضَى بِهِ الصَّالِحُونَ فَإِنْ جَاءَ أَمْرٌ لَيْسَ فِي كِتَابِ اللَّهِ وَلاَ قَضَى بِهِ نَبِيُّهُ ﷺ وَلاَ قَضَى بِهِ الصَّالِحُونَ فَلْيَجْتَهِدْ رَأْيَهُ وَلاَ يَقُولُ إِنِّي أَخَافُ وَإِنِّي أَخَافُ فَإِنَّ الْحَلاَلَ بَيِّنٌ وَالْحَرَامَ بَيِّنٌ وَبَيْنَ ذَلِكَ أُمُورٌ مُشْتَبِهَاتٌ فَدَعْ مَا يَرِيبُكَ إِلَى مَا لاَ يَرِيبُكَ قَالَ أَبُو عَبْدِ الرَّحْمَنِ هَذَا الْحَدِيثُ جَيِّدٌ جَيِّدٌ  

"There was a time when we did not pass so many judgments, but now that time is over. Now Allah, the Mighty and Sublime, has decreed that we reach a time when, as you see, (we are asked to pass many judgments). Whoever among you is asked to pass a judgment after this day, let him pass judgment according to what is in the Book of Allah. If he is faced with a matter that is not mentioned in the Book of Allah, let him pass judgment according to the way His Prophet [SAW] passed judgment. If he is faced with a matter that is not mentioned in the Book of Allah, and concerning which His Prophet did not pass judgment, then let him pass judgment according to the way the righteous passed judgment. And let him not say 'I am afraid, I am afraid.' For that which is lawful is clear and that which is unlawful is clear, and between them are matters which are not as clear. Leave that which makes you doubt for that which does not make you doubt."  

أَتَى عَلَيْنَا حِينٌ وَلَسْنَا نَقْضِي وَلَسْنَا هُنَالِكَ وَإِنَّ اللَّهَ ﷻ قَدَّرَ أَنْ بَلَغْنَا مَا تَرَوْنَ فَمَنْ عَرَضَ لَهُ قَضَاءٌ بَعْدَ الْيَوْمِ فَلْيَقْضِ فِيهِ بِمَا فِي كِتَابِ اللَّهِ فَإِنْ جَاءَ أَمْرٌ لَيْسَ فِي كِتَابِ اللَّهِ فَلْيَقْضِ بِمَا قَضَى بِهِ نَبِيُّهُ فَإِنْ جَاءَ أَمْرٌ لَيْسَ فِي كِتَابِ اللَّهِ وَلَمْ يَقْضِ بِهِ نَبِيُّهُ ﷺ فَلْيَقْضِ بِمَا قَضَى بِهِ الصَّالِحُونَ وَلاَ يَقُولُ أَحَدُكُمْ إِنِّي أَخَافُ وَإِنِّي أَخَافُ فَإِنَّ الْحَلاَلَ بَيِّنٌ وَالْحَرَامَ بَيِّنٌ وَبَيْنَ ذَلِكَ أُمُورٌ مُشْتَبِهَةٌ فَدَعْ مَا يَرِيبُكَ إِلَى مَا لاَ يَرِيبُكَ  

He wrote to 'Umar, to ask him (a question), and 'Umar wrote back to him telling him: "Judge according to what is in the Book of Allah. If it is not (mentioned) in the Book of Allah, then (judge) according to the Sunnah of the Messenger of Allah [SAW]. If it is not (mentioned) in the Book of Allah or the Sunnah of the Messenger of Allah [SAW], then pass judgment according to the way the righteous passed judgment. If it is not (mentioned) in the Book of Allah, or the Sunnah of the Messenger of Allah [SAW], and the righteous did not pass judgment concerning it, then if you wish, go ahead (and try to work it out by yourself) or if you wish, leave it. And I think that leaving it is better for you. And peace be upon you."  

أَنَّهُ كَتَبَ إِلَى عُمَرَ يَسْأَلُهُ فَكَتَبَ إِلَيْهِ أَنِ اقْضِ بِمَا فِي كِتَابِ اللَّهِ فَإِنْ لَمْ يَكُنْ فِي كِتَابِ اللَّهِ فَبِسُنَّةِ رَسُولِ اللَّهِ ﷺ فَإِنْ لَمْ يَكُنْ فِي كِتَابِ اللَّهِ وَلاَ فِي سُنَّةِ رَسُولِ اللَّهِ ﷺ فَاقْضِ بِمَا قَضَى بِهِ الصَّالِحُونَ فَإِنْ لَمْ يَكُنْ فِي كِتَابِ اللَّهِ وَلاَ فِي سُنَّةِ رَسُولِ اللَّهِ ﷺ وَلَمْ يَقْضِ بِهِ الصَّالِحُونَ فَإِنْ شِئْتَ فَتَقَدَّمْ وَإِنْ شِئْتَ فَتَأَخَّرْ وَلاَ أَرَى التَّأَخُّرَ إِلاَّ خَيْرًا لَكَ وَالسَّلاَمُ عَلَيْكُمْ