One symbolizes wholeness, uniqueness, and individualism. It is also an symbol of marriage, two beings joined as one. Number three , It represents completeness. Three is especially important during Rosh Hashana, the shofar is sounded three times in combinations of three different notes. One note, Tekiah has a single blast, shevarim, three blasts, and teruah, nine blasts.
Jewish festivals conclude with the appearance of three stars in the evening sky.
Hamentashen is a three cornered pastry for Purim. Jacob had four wives, Rachel, Leah, Bilhah and Zilpah who gave birth to the Twelve Tribes, ancestors of the Jewish people. The Torah has Five Books of Moses which is also known as the Pentateuch. An apple has five seeds. Both Sukkot and Passover are seven day holidays, the Torah portion is divided into seven sections.