Sayyiduna Jarir (may Allah be pleased with him) said: "I pledged allegiance to the Messenger of Allah (peace and blessings be upon him) on listening and obeying, and on sincere goodwill towards every Muslim." So whenever he bought or sold something, he would say to the other party: Know that what I am taking from you is dearer to me than what we have given you, so make your choice.
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 2401