When Moshe Rabbeinu was living in Yisro's home in Midyan, Hashem told Moshe to return to Mitzrayim to redeem the Yidden from slavery. The Midrash (Tanchuma, Shemos 16) tells us that Moshe replied, "Ribono Shel Olam, how can I leave Yisro without first asking his consent? Yisro opened his home for me; he treats me like his son." The Midrash explains, "When one opens his house for you, you owe him your life... You are obligated to honor the one who opened his home for you more than you are obligated to honor your father and mother." Despite the urgent need to save the Jewish nation, Moshe said it wasn't right to leave Midyan without Yisro's consent because Yisro hosted him in his home. This is another example of how much hakaras hatov we need to have.
The Imrei Emes concluded, "If this is the punishment for doing bad to someone who did kindness to you, certainly when you do kindness to a person who performed bad to you, goodness will never depart from your home!"
