A stoic quote by Epictetus from Discourses III, 20.9

A boxer derives the greatest advantage from his sparring partner – and my accuser is my sparring partner. He trains me in patience, civility and even temper.
― Epictetus Discourses III, 20.9

Stoic Sage in Training

A Sage is a theoretical perfect stoic - I can only attempt to act as I imagine he would act in my situation.