Hasan bin Ayyoob Al-Baghdaadi (rahimahullah) narrates that a person once said to Imaam Ahmed bin Hambal (rahimahullah), “O Abu ‘Abdillah! May Allah Ta‘ala keep you alive upon Islam!” Hearing this du‘aa, Imaam Ahmed (rahimahullah) immediately responded, “Not only upon Islam, but also upon the Mubaarak Sunnah of Rasulullah (sallallahu ‘alaihi wasallam).”
(Manaaqib Imaam Ahmed libnil Jowzi pg. 243)
Abu Bakr Khallaal (rahimahullah) narrates that one of Imaam Ahmed (rahimahullah)’s students mentioned the following:
Imaam Ahmed (rahimahullah) once said to me, “I did not write any Hadith from Rasulullah (sallallahu ‘alaihi wasallam) except that I also practiced upon it, to the extent that I came across the Hadith which mentions that Nabi (sallallahu ‘alaihi wasallam) underwent cupping and thereafter gave Abu Taibah (the one who carried out the cupping) a Dinar. Hence, when I underwent cupping, I gave a Dinar to the one who had carried out the cupping.”
(Manaaqib Imaam Ahmed libnil Jowzi pg. 246)