Muwatta Malik, Book 54, Hadith 26 (USC-MSA)

Malik related to me from Humayd at-Tawil that Anas ibn Malik said, "The Messenger of Allah, may Allah bless him and grant him peace, was cupped. Abu Tayba cupped him, and the Messenger of Allah, may Allah bless him and grant him peace, ordered him to be given a sa of dates and ordered his family to lessen what he paid them for his kitaba or kharaj."

حَدَّثَنِي مَالِكٌ، عَنْ حُمَيْدٍ الطَّوِيلِ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّهُ قَالَ احْتَجَمَ رَسُولُ اللَّهِ صلى الله عليه وسلم حَجَمَهُ أَبُو طَيْبَةَ فَأَمَرَ لَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم بِصَاعٍ مِنْ تَمْرٍ وَأَمَرَ أَهْلَهُ أَنْ يُخَفِّفُوا عَنْهُ مِنْ خَرَاجِهِ ‏.‏

sunnah.com

also referenced under: Book 54, Hadith 1791 (In-Book)