Abu Salamah Khuzaa‘ee (rahimahullah) mentions:

Whenever Imaam Maalik (rahimahullah) intended to go and narrate the Ahaadith of Rasulullah (sallallahu ‘alaihi wasallam), he would first perform wudhu, as a person performs wudhu for salaah. He would also wear his best clothing, wear a topi and comb his beard. When somebody asked him the reason for this, he replied, “I do this to honor the Ahaadith of Rasulullah (sallallahu ‘alaihi wasallam).”

(Tahzeebul Kamaal 27/110)