And God said,
Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.
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Tertullian of Carthage
What of the fact that waters were in some way the regulating powers by which the disposition of the world thenceforward was constituted by God? For the suspension of the celestial firmament in the midst He caused by "dividing the waters;" the suspension of "the dry land" He accomplished by "separating the waters." After the world had been hereupon set in order through its elements, when inhabitants were given it, "the waters" were the first to receive the precept "to bring forth living creatures." Water was the first to produce that which had life, that it might be no wonder in baptism if waters know how to give life. For was not the work of fashioning man himself also achieved with the aid of waters? Suitable material is found in the earth, yet not apt for the purpose unless it be moist and juicy; which (earth) "the waters," separated the fourth day before into their own place, temper with their remaining moisture to a clayey consistency.[On Baptism 3]