humash, Genesis. 1. 5.). Light and darkness had to be separated not just because light was deemed good but also because there purposes are so different, that they are not able to function together continuously, one is needed to bring the other in. We can also look at the nature of light and darkness, darkness absorbs light always, where as true light in relation to darkness is not accepting thus it is obstinate, it is easier for us to be darkness that accepts light and not falter then it is for us to try and emulate the light.
             "G-d said, 'Let there be a firmament in the midst of the waters, and let it separate between water and water.' So G-d made the firmament, and separated between the waters, which were beneath the firmament, and the waters, which were above the firmament. And it was so. G-d called to the firmament: 'Heaven.' And there was evening and there was a morning, a second day." (The Chumash, Genesis. 1. 6-8.). G-d separates the heaven from the earth again so that both could fulfill their intended functions the earth as nurturer and the heavens as Creator. The Earth always accepts Heaven's decrees.
             "G-d said, 'Let the earth sprout vegetation: herbage yielding seed,
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