Sayyiduna Abdullah (may Allah be pleased with him) said: When Islam appeared, the first to declare their Islam were seven people: the Prophet (peace and blessings be upon him), Abu Bakr, Ammar, Sumayyah, Suhayb, Bilal and al-Miqdad (may Allah be pleased with them). Allah Almighty protected the Prophet (peace and blessings be upon him) through his uncle, and Abu Bakr (may Allah be pleased with him) through his people. But the rest were seized by the polytheists and severely tormented: they would be made to wear iron armour and thrown out in the sun, and every one of them gave in to the polytheists' demands except Bilal (may Allah be pleased with him). He regarded his own self as worthless for the sake of Allah, and his people held him in contempt. He would be handed over to boys, who would drag him around the streets of Makkah while he called out only: "Ahad, Ahad" (One, One).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المرتد / 16897