Sahih Bukhari | Volume 3 | Hadith Number 293

Narrated by Hakim bin Hizam
Allah's Apostle said, "The seller and the buyer have the right to keep or return goods as long as they have not parted or till they part; and if both the parties spoke the truth and described the defects and qualities (of the goods), then they would be blessed in their transaction, and if they told lies or hid something, then the blessings of their transaction would be lost."