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The outermost orb contained the stars and the term firmament was then transferred to this orb. This cosmology involved celestial orbs, nested concentrically inside one another, with the earth at the center. The Medieval Scholastics adopted a cosmology that fused the ideas of the Greek philosophers Aristotle and Ptolemy. The Greeks and Stoics adopted a model of celestial spheres after the discovery of the spherical Earth in the 4th to 3rd centuries BCE. Such a doctrine of accommodation allowed Christians to accept the findings of science without rejecting the authority of scripture. "As it became a theologian, had to respect us rather than the stars", Calvin wrote. "He who would learn astronomy and other recondite arts, let him go elsewhere", wrote Calvin. In 1554 John Calvin proposed interpreting the "firmament" as clouds. The Copernican Revolution of the 16th century led to reconsideration of these matters. According to Saint Thomas Aquinas (1225-1274) the firmament had a "solid nature" and stood above a "region of fire, wherein all vapor must be consumed". Saint Basil (330-379) argued for a fluid firmament. "We may understand this name as given to indicate not it is motionless but that it is solid", he wrote. Augustine (354-430) considered that too much learning had been expended on the nature of the firmament. Cosmas described a flat rectangular world surrounded by four seas at the far edges of the seas, four immense vertical walls supported a vaulted roof, the firmament, above which in a further vaulted space lived angels who moved the heavenly bodies and controlled rainfall from a vast cistern. The 6th-century Egyptian traveller, Cosmas Indicopleustes, formulated a detailed Christian view of the universe, based on various Biblical texts and on earlier theories by Theophilus of Antioch (2nd century CE) and by Clement of Alexandria ( c. So slight is this elevation that birds may rise to it and fly along its expanse. To this vault are fastened the lights, the stars. Over this is arched the solid vault of heaven. The Hebrews regarded the earth as a plain or a hill figured like a hemisphere, swimming on water. Like most ancient peoples, the Hebrews believed the sky was a solid dome with the Sun, Moon, planets and stars embedded in it. Rāqîa derives from the root raqqəʿ ( רָקַע), meaning "to beat or spread out thinly", e.g., the process of making a dish by hammering thin a lump of metal. The word "firmament" translates shamayim ( שָׁמַיִם) or rāqîaʿ ( רָקִ֫יעַ), a word used in Biblical Hebrew.
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The caption underneath the engraving (not shown here) translates to "A medieval missionary tells that he has found the point where heaven and Earth meet." The Flammarion engraving (1888) depicts a man crawling under the edge of the sky, depicted as if it were a solid hemisphere, to look at the mysterious Empyrean beyond.
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