Allah, the Blessed and Exalted, says: "When believing women come to you as emigrants, examine them. Allah knows best about their faith. Then if you know them to be believers, do not return them to the disbelievers; neither are they (the women) lawful for them (the disbelievers), nor are they (the disbelievers) lawful for them." [Surah al-Mumtahanah: 10]
Imam al-Shafi'i (may Allah have mercy on him) said: "Some of the scholars who have knowledge of the Qur'an hold that this verse was revealed about a woman emigrant from among the people of Makkah, and some of them named her as the daughter of Uqbah bin Abi Mu'ayt (Sayyidah Umm Kulthum (may Allah be pleased with her)). The people of Makkah were idol-worshippers. And (they hold) that the saying of Allah Almighty, 'And do not hold on to the marriage ties of disbelieving women' [Surah al-Mumtahanah: 10], was revealed about a believing male emigrant from among the people of Makkah, and that it (this verse) was revealed during the period of the truce (of Hudaybiyah)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / Q13970