And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
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Basil the Great
In fact, there did exist something, as it seems, even before this world which our mind can attain by contemplation but which has been left uninvestigated because it is not adapted to those who are beginners and as yet infants in understanding. This was a certain condition older than the birth of the world and proper to the supramundane powers, one beyond time, everlasting, without beginning or end. In it the Creator and Producer of all things perfected the works of his art, a spiritual light befitting the blessedness of those who love the Lord, rational and invisible natures, and the whole orderly arrangement of spiritual creatures which surpass our understanding and of which it is impossible even to discover the names. These fill completely the essence of the invisible world.