Rabbi Moshe of Kobrin told his followers that even if they make serious mistakes, they should not be discouraged. Rather, they should focus on correcting themselves in the future. To illustrate this point, he asked a disciple of his who grew up on a farm, "Did you use to ride on a horse?"
"Yes," replied the man, "quite frequently."
"Did it ever happen that you fell off the horse?" asked Rabbi Moshe.
"Many times," the disciple said.
"And what did you do?" Rabbi Moshe asked.
"I just mounted the horse again, and continued riding," was the person's reply.
"This is a model how we should react to our mistakes," Rabbi Moshe told his followers. "Never give up. Regardless of how many times you fall, keep on trying."
(Ohr Yeshorim, p.108; Gateway to Happiness, p.379)