"Blessed art Thou, LORD our God, King of the universe, who brings forth bread from the earth" is the traditional blessing made by Jews before eating bread.  It is also one of the most significant blessings in the Jewish religion, one said by the head of the household before any festive meal. In the desert, after the Exodus from Egypt, the manna did not fall on Shabbat. Instead, a double portion fell on Friday. By using two loaves of challah at Shabbat meal, we remind ourselves of the sanctity of Shabbat and that God will provide for our material needs! (Exodus 16:4-30).