The real struggle for moral liberty started the day after the exodus from Egypt. The first day was a given; it was the day of God, not of the people. It was the day of passivity and complete surrender. Only the next day did the spiritual labor of the human being begin, and that is therefore the first day of our spiritual elevation.
Nothing is more dangerous for a person than to remain spiritually stale, and we are therefore required to count the 49 days of the Omer. In order to prepare ourselves for the upcoming celebration of Shavuot and the giving of the Torah, we are asked to climb a ladder of 49 spiritual steps, each day adding another dimension to our souls.