Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
ibnmajah:2230ʿAlī b. Maymūn al-Raqqī > ʿAbdullāh b. Yazīd > Ibn Lahīʿah > Mūsá b. And Rdān > Saʿīd b. al-Musayyab > ʿUthmān b. ʿAffān

"I used to sell dates in the marketplace, and I would say: 'This was such and such an amount (when I bought it).' I Would give the purchaser a specific amount of dates according to the way it had been measured for me, and take my profit. Then I began to have some doubts about that, so I asked the Messenger of Allah ﷺ, and he said: ‘When you name the amount, measure it in front of the purchaser."'  

ابن ماجة:٢٢٣٠حَدَّثَنَا عَلِيُّ بْنُ مَيْمُونٍ الرَّقِّيُّ حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يَزِيدَ عَنِ ابْنِ لَهِيعَةَ عَنْ مُوسَى بْنِ وَرْدَانَ عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ عَنْ عُثْمَانَ بْنِ عَفَّانَ قَالَ

كُنْتُ أَبِيعُ التَّمْرَ فِي السُّوقِ فَأَقُولُ كِلْتُ فِي وَسْقِي هَذَا كَذَا فَأَدْفَعُ أَوْسَاقَ التَّمْرِ بِكَيْلِهِ وَآخُذُ شِفِّي فَدَخَلَنِي مِنْ ذَلِكَ شَىْءٌ فَسَأَلْتُ رَسُولَ اللَّهِ ﷺ فَقَالَ إِذَا سَمَّيْتَ الْكَيْلَ فَكِلْهُ  


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Collected by Suyūṭī
suyuti:3-59b
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السيوطي:٣-٥٩b

"كُنْتُ أَبِيعُ التَّمرَ فِى سُوقِ بَنِى قَيْنُقَاعَ فَأَكَيلُ أَوْسَاقًا فَأَقُولُ: كِلْتُ فِى وَسْقِى كَيْتَ وَكَيْتَ، فَدَخَلَنِى شَىْءٌ مِنْ ذَلِكَ فَأَتَيْتُ النَّبِىَّ ﷺ فَقَالَ: إِذَا سَمَّيْتَ كَيلًا فَكلْهُ".  

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