When Rabbi Moshe of Korbin was seven years old, there was a severe famine in Lithuania. Poor people wandered from village to village in search of food. Many of them flocked to the home of Rav Moshe’s mother, who readily cooked and baked for them.
Once a very large number of the poor came to her home and she had to cook for them in shifts. When some individuals grew impatient and insulted her, she began to cry, since she felt that she was doing her utmost for them.
Her young son, the future Rabbi of Korbin, said to her, “Why should their insults trouble you? Don’t their insults help you perform the mitzvah with sincerity? If they had praised you, your merit would be less, since you might be doing the kindness to gain their praise, rather than to fulfill the Almighty’s command.” ~ Ohr Yeshorim as quoted by R’ Zelig Pliskin