Ash-Shama'il Al-Muhammadiyah, Book 49, Hadith 346 (English) ⓘ

Ibn 'Umar Radiyallahu 'Anhu reports: "Rasulullah Sallallahu 'Alayhi Wasallam called a hajjaam, who treated Rasulullah Sallallahu 'Alayhi Wasallam. Rasulullah Sallallahu 'Alayhi Wasallam inquired from him what tax or duty did he have to pay daily? He replied, three saa'. Rasulullah Sallallahu 'Alayhi Wasallam had it reduced to two saa', and gave him his remuneration".

حَدَّثَنَا هَارُونُ بْنُ إِسْحَاقَ، قَالَ‏:‏ حَدَّثَنَا عَبْدَةُ، عَنِ ابْنِ أَبِي لَيْلَى، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم، دَعَا حَجَّامًا فَحَجَمَهُ وَسَأَلَهُ‏:‏ كَمْ خَرَاجُكَ‏؟‏ فَقَالَ‏:‏ ثَلاثَةُ آصُعٍ، فَوَضَعَ عَنْهُ صَاعًا وَأَعْطَاهُ أَجْرَهُ‏.‏