Abdullah, who was one of the people of Hims, says: I saw Abu al-Darda' (may Allah be pleased with him) bargaining with a man over a goat. The man swore that he would not sell it, then later said: I will sell it. Abu al-Darda' (may Allah be pleased with him) refused to buy the goat from him, saying: I do not want to push you into sin.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأيمان / 19867