Before the Fall the waters were one dimensional—they gave life. After the Fall, another dimension is added. The waters kill/drown and they give life. This becomes the New Testament language of Baptism.
At the foot of Mt. Sinai, God told Israel how to celebrate Pentecost once they reached the holy land. Generations later, on the day of this Old Testament festival, Christ poured out his Spirit in Jerusalem. What made Pentecost the ideal day for this gift to be given?