عَن يَحْيَى بْنِ عَبْدِ الرَّحْمَنِ قَالَ: إِنَّ عُمَرَ بن الْخطاب
خَرَجَ فِي رَكْبٍ فِيهِمْ عَمْرُو بْنُ الْعَاصِ حَتَّى وَرَدُوا حَوْضًا فَقَالَ عَمْرُو: يَا صَاحِبَ الْحَوْضِ هَلْ تَرِدُ حَوْضَكَ السِّبَاعُ فَقَالَ عُمَرُ بْنُ الْخَطَّابِ يَا صَاحِبَ الْحَوْضِ لَا تُخْبِرْنَا فَإِنَّا نَرِدُ عَلَى السِّبَاعِ وَتَرِدُ عَلَيْنَا
Umar went out with a party of riders among whom was Amr b al-‘As. When they came to a cistern and Amr asked its owner whether beasts of prey came down to it, Umar said, ‘Don’t tell us, owner of the cistern, for we go down to what beasts of prey leave, and they go down to what we leave.’ Malik transmitted it and Razin made an addition saying that some transmitters add to Umar’s words that he said he had heard God’s messenger say, ‘They have in their bellies what they have taken, and what remains is pure for us and drinkable.’’