The Messenger of Allah ﷺ was cupped and gave the cupper his wages. Had he known it to be unlawful, he would not have given it to him.
حدثنا مسدد حدثنا يزيد بن زريع حدثنا خالد عن عكرمة
احتجم رسول الله ﷺ وأعطى الحجام أجره ولو علمه خبيثا لم يعطه
Musaddad transmitted it from Bukhari, in the Book of Hiring, Chapter on the Wages of the Cupper, hadith no. 2279.