Khabbab said, "I was a blacksmith in the days before Islam, and Aas bin Waail owed me a debt, so I went to him to collect it.He said, "I will not pay you until you renounce Muhammad ﷺ."I said, "I will not renounce him until Allah causes you to die and then raises you up again."He said, "Then leave me alone until I die and am raised up, for I shall be given wealth and children, and then I will settle your debt with you."So this was revealed, "Have you seen the one who disbelieved in Our signs and said, 'I shall surely be given wealth and children'? Has he gained knowledge of the unseen, or has he taken a covenant with the Most Merciful?" [Maryam 19:77–78].
كنت قينا في الجاهلية، وكان لي على العاص بن وائل دين، فأتيته أتقاضاه. قال: لا أعطيك حتى تكفر بمحمد ﷺ، فقلت: لا أكفر حتى يميتك الله، ثم تبعث. قال: دعني حتى أموت وأبعث فسأوتي مالا وولدا فأقضيك، فنزلت: {أفرأيت الذي كفر بآياتنا وقال لأوتين ما لا وولدا أطلع الغيب أم اتخذ عند الرحمن عهد} [سورة مريم: ٧٧-٧٨].
Bukhari related it in the Book of Sales (2091), and Muslim in the Book on the Traits of Hypocrites (2795), both through the route of Sulayman Amash, from Abu Duha, from Masruq, from Khabab, who related it.His saying, "I was a qayn," Ibn Duraid said, the original meaning of qayn is a blacksmith, and then among the Arabs every craftsman came to be called a qayn. Zajjaj said, the qayn is one who sharpens spearheads, and the qayn is also a blacksmith. See Fath al-Bari (4/318).