A man from the Ansar apostatized from Islam and joined the polytheists, so Allah the Exalted revealed, "How shall Allah guide a people who disbelieved after their belief" [Al Imran 3:86] until the end of the verse. His people sent it to him, and he returned in repentance. The Prophet ﷺ accepted that from him and let him go.
حدثنا علي بن عاصم عن داود بن أبي هند عن عكرمة
أن رجلا من الأنصار ارتد عن الإسلام ولحق بالمشركين فأنزل الله تعالى {كيف يهدي الله قوما كفروا بعد إيمانهم} إلى آخر الآية فبعث بها قومه فرجع تائبا فقبل النبي ﷺ ذلك منه وخلى عنه
Its isnad is sahih. Tabari also related it via Yazid bin Zuray from Dawud bin Abu Hind, as Ibn Kathir cited in his tafsir 2:181, then he said, "Nasai, Hakim, and Ibn Hibban likewise related it via Dawud bin Abu Hind." Hakim said, "Its isnad is sahih, but the two of them (Bukhari and Muslim) did not narrate it."