Prefigurations of Baptism in the Old Covenant
Since the beginning of the world, water, so humble and wonderful a creature, has been the source of life and fruitfulness. Sacred Scripture sees it as "oveshadowed" by the Spirit of God:
At the very dawn of creation
your Spirit breathed on the waters,
making them the wellspring of all holiness.
Source: Catechism of the Catholic Church (Vatican.va)