The Conversion of Ḍimād:

Dāwūd ibn Abī Hind narrated from ʿAmr ibn Saʿīd, from Saʿīd ibn Jubayr, from Ibn ʿAbbās, who said:

Ḍimād arrived in Mecca—he was from the clan of Azd Shanūʿah—and he used to recite protective supplications (ruqya) for those afflicted by evil winds. He heard some of the foolish people saying, “Muhammad is mad,” so he said, “I shall go to this man; perhaps Allah will cure him through me.”

He continued: I met Muhammad and said, “I recite ruqya for these winds, and Allah heals through my hands whomever He wills. Come, then, that I may treat you.”

Muhammad replied, “Indeed, all praise belongs to Allah; we praise Him and seek His help. Whomever Allah guides none can mislead, and whomever He leads astray none can guide. I bear witness that there is no deity but Allah, alone, without partner”—he repeated this three times—“and that Muhammad is His servant and Messenger. To proceed:

Ḍimād said, “By Allah, I have heard the speech of soothsayers, sorcerers, and poets, yet I have never heard words like these; they have reached the very depths of the sea. Give me your hand so that I may pledge allegiance to you upon Islam.” The Messenger of Allah ﷺ accepted his pledge and said to him, “And for your people as well.” He replied, “And for my people.”

Later the Messenger of Allah ﷺ dispatched an expedition that passed by the tribe of Ḍimād. The commander asked the detachment, “Have you taken anything from these people?” One of them replied, “I took a waterskin from them.” He said, “Return it to them, for they are the people of Ḍimād.”

Related by Muslim.