Mahmud bin Labid (may Allah have mercy on him), who was one of Banu Abd al-Ashhal, said: When Abu al-Haysar Anas bin Rafi' came to Makkah, and with him were some young men of Banu Abd al-Ashhal, among them Sayyiduna Iyas bin Mu'adh (may Allah be pleased with him), they were seeking an alliance with Quraysh against their own people, the Khazraj. The Messenger of Allah (peace and blessings be upon him) learned of them, so he (peace and blessings be upon him) came to them and sat with them, and said: "Would you be interested in something better than what you have come for?" They said: "What is that?" He (peace and blessings be upon him) said: "I am the Messenger of Allah. He has sent me to the servants to call them to worship Him alone and not to associate anyone with Him, and Allah has revealed the Book to me." Then he (peace and blessings be upon him) taught them Islam and recited the Qur'an to them. Sayyiduna Iyas bin Mu'adh (may Allah be pleased with him), who was still a young man, said: "O my people! By Allah, this is better than what you came for." At that, Abu al-Haysar Anas bin Rafi' took a handful of the soil of al-Batha' and threw it in Iyas's face, and said: "Leave us alone! By my life, we have come for something other than this." Iyas fell silent, and the Messenger of Allah (peace and blessings be upon him) got up and left them, and they went back to Madinah. Then the Battle of Bu'ath took place between the Aws and the Khazraj. Soon after that, Iyas bin Mu'adh passed away. Mahmud bin Labid said: "Those of his people who were present at his death told me that they kept hearing him declaring the oneness of Allah, proclaiming His greatness, praising Him and glorifying Him until he died, and they had no doubt that he died a Muslim. He had already felt Islam in his heart in that very gathering when he heard from the Messenger of Allah (peace and blessings be upon him) what he heard."
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 801