وَقَالَ أَحْمَدُ بْنُ شَبِيبِ بْنِ سَعِيدٍ حَدَّثَنَا أَبِي، عَنْ يُونُسَ، عَنِ ابْنِ شِهَابٍ، عَنْ خَالِدِ بْنِ أَسْلَمَ، قَالَ خَرَجْنَا مَعَ عَبْدِ اللَّهِ بْنِ عُمَرَ فَقَالَ هَذَا قَبْلَ أَنْ تُنْزَلَ، الزَّكَاةُ، فَلَمَّا أُنْزِلَتْ جَعَلَهَا اللَّهُ طُهْرًا لِلأَمْوَالِ.
Narrated Khãlid bin Aslam: Wewent out with 'Abdullãh bin 'Umar and hesaid, "This (Verse) was revealed before theprescription of Zakat, and when Zakãt wasprescribed, Allah made it a means ofpurifying one's wealth." Translation Not Available
Book Ref: Sahih Bukhari Book 65 Hadith 4661
Web Ref: Sahih Bukhari Vol 1 Book 60 Hadith 183