Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) says that the Messenger of Allah (peace and blessings be upon him) "forbade al-muzabanah (muzabanah)", and muzabanah is that a man sells the fruit of his date palms by measure: if it turns out more, it is mine, and if it turns out less, it is on me.
(b) In the narration of Arim: that he sells fresh dates by measure.
(c) Sayyiduna Zayd bin Thabit (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) "granted a concession in the araya sale by estimation."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10636