In a well known incident, someone who had driven R’ Moshe Feinstein zt”l to yeshivah accidentally slammed the car door shut on R’ Moshe’s fingers. R’ Moshe clenched his fingers with his other hand, bit his lips against the excruciating pain and walked into the yeshiva building without uttering a sound.
Later, several talmidim who had witnessed the incident asked R’ Moshe why he had restrained himself so. He answered quietly, “The young man was kind enough to drive me to yeshivah. Could I hurt his feelings by letting him know something was wrong?” ~ 5 Great Lives