Rashi on Exodus 3:10/רש"י על שמות ג׳:י׳

1ועתה לך ואשלחך אל פרעה COME NOW, THEREFORE, AND I WILL SEND THEE UNTO PHARAOH — And if you ask “What will this avail?” והוצא את עמי AND BRING FORTH MY PEOPLE — your words will prove effective and you will bring them forth from there.