Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said: People used to dislike giving even a little benefit to their relatives while they were polytheists, so this blessed verse was revealed: "Their guidance is not your responsibility, but Allah guides whom He wills" [Surah al-Baqarah: 272], up to: "and you will not be wronged" [Surah al-Baqarah: 272]. He said: Then permission was granted to them.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7842