Zahdam bin Madrab, Abu Muslim زهدم بن مضرب أبو مسلم الجرمي · The Book of Oaths and Vows

"The Messenger of Allah said: 'Whoever swears by a religion other than Islam, telling a lie, will be as he said.'" In his narration, Qutaibah said: "Intentionally." Yazid said: "Telling a lie will be as he said, and whoever kills himself with something. Allah will punish him with it in the Fire of Hell."

"In Al-Madinah we used to buy and sell Wasqs (of goods), and we used to call ourselves Samasir (brokers), and the people used to call us like that. The Messenger of Allah came out to us one day, and called us by a name that was better than that which we called ourselves and which the people called us. He said: 'O Tujjar (traders), your selling involves (false) oaths and lies, so mix some charity with it.'"