51:16Adh-Dhaariyat

Hakim bin Hizam said, "O Allah's Messenger (ﷺ)! I used to do good deeds in the Pre-Islamic period of Ignorance, e.g., keeping good relations with my Kith and kin, manumitting slaves and giving alms. Shall I receive a reward for all that?" Allah's Messenger (ﷺ) replied, "You embraced Islam with all the good deeds which you did in the past."

I said to Allah's Messenger (ﷺ), "Before embracing Islam I used to do good deeds like giving in charity, slave-manumitting, and the keeping of good relations with Kith and kin. Shall I be rewarded for those deeds?" The Prophet (ﷺ) replied, "You became Muslim with all those good deeds (Without losing their reward)."

That he said, "O Allah's Messenger (ﷺ)! 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 Messenger (ﷺ) said, "You have embraced Islam with all those good deeds which you did.

That the Prophet (ﷺ) used to accept a gift and make return for it.

From the Prophet (ﷺ), that Kisra sent him a gift so he accepted, and that kings gave him gifts and he accepted them. There is something about this from Jabir. This is a Hasan Gharib Hadith. Thuwair (a narrator in the chain) is Ibn Abi Fakhitah, whose name was Sa'eed bin 'Illaqah, and Thuwair's Kunyah was Abu Jahm.