Rav Avira said (sometimes he said it in the name of Rabbi Ami, and sometimes in the name of Rabbi Asi – because he heard it from both): Ministering angels said to the Holy One Blessed Is He, “Master of the World! In your own Torah you have written, 'Do not show favoritism, and do not take bribe,' but you show favoritism to Israel, as you yourself say in your Torah, 'May God show favor to you and turn His face to you.'”
God answered, “What can I do? How can I not show them favor! I told them in the Torah, 'You will eat and be satisfied and bless God.' I told them to eat their fill, and only then bless God, and they are exacting with themselves, and bless Me when they eat an olive volume, and an egg's volume. The person's body is not satisfied until he eats his fill. However, these righteous understood 'and be satisfied' as 'be a little satisfied,' and interpreted My words as in regards to the soul, not the body. Do you remember how we created the world? I was for it, and you were against, and really you, the angels, were right: I should not have created the world. However, I saw the souls of the righteous, fell in love with them, and created the world against logic. How can I not show favor to them now?”
We see from here that when a person eats little, and understands a minor satisfaction as being enough, this causes the awakening of God's favor for him.
Art: Jozef Israels - The Frugal Meal