Yahya related to me from Malik from Abdullah ibn Dinar from Abdullah ibn Umar that a man mentioned to the Messenger of Allah, may Allah bless him and grant him peace, that he was always being cheated in business transactions. The Messenger of Allah, may Allah bless him and grant him peace, said, "When you enter a transaction, say, 'No trickery.' So whenever that man entered a transaction, he would say, 'No trickery.' "
Muwatta Malik Book 31, Hadith 99
← Previous Hadith Malik said, from Nafi from Abdullah ibn Umar that the Messenger of Allah, may Allah bless him and grant him peace, forbade najsh.

Malik said, "Najsh is to offer a man more than the worth of his goods when you do not mean to buy them and someone else follows you in bidding."

Muwatta Malik Book 31, Hadith 98 Next Hadith → Malik related to me that Yahya ibn Said heard Said ibn al- Musayyab say, "When you come to a land where they give full measure and full weight, stay there. When you come to a land where they shorten the measure and weight, then do not stay there very long."

Muwatta Malik Book 31, Hadith 100