Their acts are well known (8)
I believe the answer is:
apostles
If this is the answer I cannot explain how the clue works.
Can you help me to learn more?
(Other definitions for apostles that I've seen before include "Early Christians" , "preachers" , "The Twelve - or a Cambridge society" , "Evangelists" , "Followers or faith teachers - the Gospels name 12" .)