Sahih Bukhari Volume 8, Book 73, Hadith Number 21.

Narated By Hakim bin Hizam : That he said, “O Allah’s Apostle! What do you think about my good deeds which I used to do during the period of ignorance (before embracing Islam) like keeping good relations with my Kith and kin, manumitting of slaves and giving alms etc; Shall I receive the reward for that?” Allah’s Apostle said, “You have embraced Islam with all those good deeds which you did.