Suppose two people fell in love and wanted to get married. One of their friends says don't bother with a fancy ceremony because it costs to much, takes too much time and you have to stand in front of all those people. It does not make a difference. Another friend however insists that the ceremony is vital for the marriage to be legitimate. Ceremonies form an important part in helping us transition from one stage of life to the next.
Marriage marks the dividing point between singleness and marriage.
Graduation marks the dividing point between being a student and being an adult. Birthday parties mark the division between being young and being older. Funerals mark our transition from our life with someone to our life without them. We often mark these times of changing from one stage of our life to another with signs symbols and ceremonies. Finally they cried out to God and He delivered them out of Egypt and brought them to the shore of the Red Sea.