Sunan Abi Dawud, Book 22, Hadith 3330 (USC-MSA) ⓘ
Narrated Suwayd ibn Qays: I and Makhrafah al-Abdi imported some garments from Hajar, and brought them to Mecca. The Messenger of Allah came to us walking, and after he had bargained with us for some trousers, we sold them to him. There was a man who was weighing for payment. The Messenger of Allah said to him: Weigh out and give overweight.
حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا سُفْيَانُ، عَنْ سِمَاكِ بْنِ حَرْبٍ، حَدَّثَنِي سُوَيْدُ بْنُ قَيْسٍ، قَالَ جَلَبْتُ أَنَا وَمَخْرَمَةُ الْعَبْدِيُّ، بَزًّا مِنْ هَجَرَ فَأَتَيْنَا بِهِ مَكَّةَ فَجَاءَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم يَمْشِي فَسَاوَمَنَا بِسَرَاوِيلَ فَبِعْنَاهُ وَثَمَّ رَجُلٌ يَزِنُ بِالأَجْرِ فَقَالَ لَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم " زِنْ وَأَرْجِحْ " .
also referenced under: Hadith 3336 (DarusSalam) & Hadith 3330 (Hasan)