Clement of Rome (fl. AD 96) echoed the cosmology of his times in his Epistle to the Corinthians , saying the heavens and the earth were created by God, and that "the heavens are moved by his direction and obey him in peace." [20:1] Likewise the sun and moon "according to his appointment circle in harmony within the bounds appointed to them."
Clement of Alexandria (c. 150-212) accepted the system of Ptolemy, with whom he was a contemporary, and used it as a basis for allegory. He related cosmology to the tabernacle of Moses.
Origen (c. 185-254) introduced the "heavenly waters" of Scripture into cosmology, and interpreted them allegorically as referring to "good angels." In a letter to Gregory, later bishop of Caesarea, Origen calls the philosophy and astronomy of the Greeks helpful for the interpretation of scripture:
And I would wish that you should take with you on the one hand those parts of the philosophy of the Greeks which are fit, as it were, to serve as general or preparatory studies for Christianity, and on the other hand so much of Geometry and Astronomy as may be helpful for the interpretation of the Holy Scriptures. The children of the philosophers speak of geometry and music and grammar and rhetoric and astronomy as being ancillary to philosophy; and in the same way we might speak of philosophy itself as being ancillary to Christianity.
Porphyry the pagan, in Against the Christians cited by Eusebius [6.19], accused Origen of mingling Grecian teachings with foreign fables, by which he meant the scriptures, that Origen interpreted as oracles with hidden meanings. Porphyry wrote:
Origen on the other hand, a Greek schooled in Greek thought, plunged headlong into un-Greek recklessness; immersed in this, he peddled himself and his skill in argument. In his life he behaved like a Christian, defying the law: in his metaphysical and theological ideas he played the Greek, giving a Greek twist to foreign tales. He associated himself at all times with Plato....
Lactantius (c. 250-325) denied that the earth has a spherical shape, on the basis of a literal interpretation of the Bible, and ridiculed the idea that antipodes could exist, because he couldn't understand how people could live on the other side of the earth "with their feet higher than their heads."
Basil (329-379) studied at the Philosophical Academy at Athens, and was Bishop of Caesarea for the last ten years of his life. Whereas Aristotle had taught the heavens were eternal, Basil argued in his Homilies on the Hexaemeron that they had been created by God, who he identified with Plato's Demiurge. [Lindberg, p. 33] Basil supposed the Creation account in Genesis spoke of two heavens, one created on the first day, and another on the second. The heavenly waters were in between. On Basil's thoughts about the waters above the firmament, Nebelsick wrote [Nebelsick, p. 94]:
The heavenly waters, that touchstone of the created nature of the heavens, caused Basil a problem but it was not insuperable. There was no doubt in Basil's mind that there were waters above the firmament as attested by the biblical account of creation. However, since the firmament appeared to be curved, the heavenly waters were likely to pour off a dome-like surface and fall to the earth. With admirable ingenuity Basil suggested that the firmament, which appears hemispherical on the underside, may, like a building enclosing a dome-shaped bath, have a flat roof.
Although the argument for the presence of and the description of the waters may seem somewhat far-fetched to us, it indicates both the seriousness with which the early Christian theologians treated the biblical account of creation and the way they used the account to break with the unacceptable idea of the division of the world into an eternal and immutable heavenly sphere and a corruptible earthly realm.
Basil supposed that since Moses gave no discussion concerning the shape of the earth and did not say, for example, that its circumference contains one hundred and eighty thousand stades, such knowledge was quite unnecessary.
Cyril of Jerusalem (d. 387) followed Basil's teaching. He wrote: "God reared the sky as a dome... and out of the fluid nature of the waters formed the stable substance of the heaven." [Nebelsick, p. 97]
Severian, Bishop of Gabala (d. after 408) lacked appreciation of the cosmology of the philosophers, and depended upon Scripture instead. Nebelsick wrote: [Nebelsick, p. 97-98]
The heaven which God created on the first day is a two-storied structure. There are waters above the heavens. The storeys themselves are divided by a ceiling in between them. The upper storey consists of fire without matter which was analogous to an angel, a spirit without a body. The lower storey is composed of fire and matter. Providence has arranged things in such a way that the heat of the fire moves downwards in order to warm the earth rather than moving upwards as is the case with fires on earth. The heaven we see is the lower heaven which was created on the second day. It is in the form of an envelope or bladder, the outside "skin" of which was composed of crystalline, congealed water to resist the fire of the sun, the moon, and the stars. The inside of the crystalline, congealed water structure is occupied by fire. For the present and until the eschaton, the water protects the heaven from dissolving or burning in the heat. On the last day, it will be used to quench the sun, moon, and stars.
On Diodore, Bishop of Tarsus (d. 394) Nebelsick wrote: [Nebelsick, p. 99]
Like Severian, Diodore relied on Scripture for his supposition that there must be two heavens. The lower heaven subsists with the earth and forms the roof of the earth. The roof of the lower heaven forms the floor of the upper one. Heaven, therefore, could not be a sphere surrounding the earth but is rather a tent or vault above it.
Eusebius Hieronymus, better known as St. Jerome, (391-406) is an important figure in this discussion of the history of the word firmament, because he translated the Bible into Latin, producing the standard text known as the Vulgate, which had a great influence in Europe in later centuries.
Before Jerome's translation appeared, several Latin versions of the scriptures were in circulation. The books of the O.T. had been translated from the Septuagint. There were major discrepancies between the various versions.
Jerome was educated in Rome, and studied under the grammmarian Aelius Donatus. He became a priest, and was secretary to Pope Damasus I from 382-385. In the year 383 Pope Damascus asked Jerome to produce a new, uniform edition of the Bible. Jerome's work was distinguished by his use of the Hebrew text, but he also had the LXX and earlier Latin versions available to him. The prefaces to his work show he was as much an editor of the earlier texts as a translator and adapter. Jerome's version of the scriptures was widely used after about the sixth century.
An ascetic, who favoured monasticism, and celibacy, he worked in a monastery in Bethlehem. Apparently, Jerome supposed that the sun and moon were living beings, and he thought biblical geography required that Jerusalem was at the center of the earth.
When it came to translating Genesis 1:8, Jerome needed a word other than "caelum" for the sky; to say "And God called the caelum caelum" would not do. The word he selected was "firmamentum," which was a reasonable translation of the Greek word "stereoma." But in Old Latin, firmamentum was not used for the sky at all. In Classical Latin, such as that of Julius Caesar, for example, "firmamentum" meant "a support", and could refer to "the strong point in an argument".
In line with accepted cosmology, Ambrose of Milan (c.339-397) believed the heaven to be a sphere. Nebelsick wrote: [Nebelsick, p. 100]
For Ambrose the firmament is the spherical heaven which divides the waters from the waters. For him, as for Basil, there was a problem as to how the waters were prevented from flowing off the domed surface of the spherical heaven. There was also a question as to why they did not spin off the swiftly revolving heavenly sphere as it circled the motionless spherical earth. Rather than answer the questions, however, Ambrose considered them too speculative to be answered. Like Basil he did add, almost as an afterthought, that it was quite usual for a building with a dome-shaped ceiling to have a flat roof. He also took comfort in the fact that it was no more difficult to conceive of the waters being suspended in the heaven than it was to conceive how the earth, which is much heavier, stayed suspended and immobile in the void. In addition to being useful as rain, however, Ambrose, again like Basil, was certain that the heavenly waters, which he finally concluded were held in the heavens by rotation, were necessary to keep the earth from being parched by the "fiery stars."
Augustine (354-430) [See biography] thought the study of astronomy was secondary to theology. He introduced an imaginative explanation for the heavenly waters. They were there, he said, to cool the fast moving sphere of Saturn. Nebelsick wrote: [Nebelsick, p. 103]
In his Commentary on Genesis, Augustine's discussion of the waters above the firmament shows a certain ingenuity. The waters are there to be sure. Their particular function was not to cool the whole of the heavens, however, but, with a reference perhaps to the astrological speculation that Saturn is cold, Augustine argued that the function of the waters is to cool Saturn. It was quite logical, as Augustine reasoned, to believe that Saturn needed cooling because of its pace. In that fast-moving objects had a tendency to be heated by friction of the air, the cooling waters would have been necessary for Saturn because, of all the planets, it had the greatest distance to travel each day. In fact, its rate of velocity around the earth is so extreme that, were it not refrigerated, it likely would be much hotter than the sun which had a much shorter distance to travel. Without the waters, then, Saturn surely would have been burned to ashes. Thus, Augustine was certain that the waters occupied heaven and that they functioned for cooling. He was not at all certain of their form, however. Two alternatives offered themselves as possibilities. They are perhaps congealed (glaciali soliditate), as Severian had thought, or they could be of the nature of vapor (vaporali tenuitate), as Basil had suggested.
The worship of the traditional pagan gods was generally abandoned in the late 4th century AD and the pagan temples demolished, statues of the gods disfigured, and the priesthoods disappeared. Some temple sites were converted to Christian shrines, and idols of various Hellenistic gods were renamed as Christian saints and martyrs.
As the religion of Christianity became the religion of the Roman Empire, lavish cathedrals were constructed in major centers. In the east, especially Syria and Palestine, these were typically domed structures. The construction of domed cathedrals in the eastern cities during this period was thought to aid the faithful to understand the nature of God the Father, as mentioned in an oration made at the dedication of a domed cathedral in Tyre, where Paulinus was Bishop, that is preserved in Eusebius [10.4]:
Such is the great cathedral which throughout the whole world under the sun the great Creator of the universe, the Word, has built, Himself again fashioning this spiritual image on earth of the vaults beyond the skies, so that by the whole creation and by rational beings on earth His Father might be honoured and worshipped.
Baldwin Smith showed that the churches and cathedrals of the east generally featured domes, reflecting the beliefs of the Christians about cosmology. He wrote [Baldwin Smith, p. 97]:
During the fifth and sixth centuries the Church, inspired by the writings of the Syrian churchmen, who attributed cosmic significance to the domical church, was desirous of cultivating the popular appeal of the celestial symbolism already connected with the domical martyrium.
A famous domical church at Edessa in Mesopotamia was called Hagia Sophia. This church was originally constructed in 313 AD, and rebuilt after a great flood in 524 AD under Justinian. It was dedicated in 537 AD. A seventh century Syrian hymn called the Sougitha which was written in praise of this building [Baldwin Smith, p. 90]:
How fully the Christians had accepted the beliefs in a cosmic house is shown by the way in which the Sougitha presents the domical church at Edessa both as the image of God and as a replica of the universe, for the "Essence," it says, resides in the Holy Temple and in effect, it is something truly remarkable that its smallness should be similar to the vast world. The Dome, which it considers to be the most remarkable and exulted part of the church is described as "comparable to the Heaven of Heaven," and ornamented with mosaics of gold, like the firmament, with brilliant stars, while its four supporting arches are "the four sides of the world."
Johannes Philoponos (c. 490-566) a teacher at the Academy in Alexandria, ventured to criticise Aristotle, saying the material of the heavens was the same as that of the earth, and that the heavens were not eternal. He made a distinction between the Creator and all his creation, showing the heavens were not divine. His arguments had considerable benefit for the future development of cosmology. [Lindberg, p. 39.]
Cosmas Indicopleustes, mentioned previously, wrote a treatise "against those who, while wishing to profess Christianity, think and imagine like the pagans that the heaven is spherical." He believed the earth was flat, and rectangular in shape. He thought heaven was constructed according to the plan of the tabernacle of Moses. He argued against Aristotle's animated planetary spheres and the daily rotation of the heavens. Instead, he proposed the heavens moved up and down, and that the sun, moon, and stars are carried along below the firmament by angels. The sun, which is smaller than the earth, moves to the north at night, and is hidden from us during its nightly journey back to its rising place in the east.
Isidore, bishop of Seville (c. 570-636) in De Natura Rerum, "filled the heavens with divine intelligences...." He followed Aristotle's onion model of nested homocentric spheres. [Nebelsick, p. 112]
Like the majority of Christian cosmologists before him, he took account of the waters above the heavens. Indeed, the name "firmament" meant for Isidore that it supported the waters and these were necessary to cool the earth lest the upper fires burned the lower elements. The waters are in the form of an icy solid. They, like the heavens themselves and like the earth, were specifically created ex nihilo. Both heaven and earth are of the stuff of creation.
Venerable Bede (c. 673-735), an English monk, took his cosmology from Pliny. The firmament divided the upper and lower heavens. The upper or superior heaven is bounded by circles, and contains water in glacial form. In the lower heaven, water has a variety of forms, and motion is irregular. He claimed the moon is larger than the sun.
Moses ben Maimon (1135-1204), a Jew from Cordova, Spain, also known as Maimonides, lived in Cairo, where he held an official post at the court of Saladin. He wrote one of the most readable philosophical treatises of the Middle Ages, Guide for the Perplexed. He placed the firmament above the atmosphere, but below the spheres of water, air, and fire, and the planetary spheres. Beyond these were the sphere of the fixed stars and the Primum Mobile. Neugebauer wrote [Neugebauer 1949, p. 336]:
Maimonides was [in many respects] a follower of Aristotlean philosophy though he had to reject the idea of an eternal existence of the world in the past because this would have eliminated the creation ex nihilo, postulated by his religion. Consequently Maimonides emphasizes the incompatibility of Aristotle's cosmic model of concentric spheres and the Ptolemaic system of eccenters and epicycles... "It is on account of my great love of truth that I have shown my embarrassment in these matters, and I have not heard, nor do I know that any of these theories have been established by proof."
William of Conches (2nd half 12th century) found the waters above the firmament contra rationem (against reason). They could not be reconciled with Aristotle's physics. According to the principles taught by Aristotle, since water is denser than air it belongs on the earth, not in the vicinity of the sphere of celestial fire. If the heavenly waters existed beyond the sphere of the stars, William reasoned, the fire would have either vaporised the waters or would have been extinguished by them. He concluded there are no waters above the heavens. The firmament is the air, and the "waters above" are suspended as vapors in clouds. [Hooykaas, p. 31]
Johannes Sacrobosco (d. 1256) an English mathematician who lived in Paris, was the author of De Sphaera, which summarized the Aristotlean-Ptolemaic system. The book remained popular for four centuries and passed through forty editions.
Robert Grosseteste (c.1170-1253) the first chancellor at Oxford, also wrote a work called De Sphaera, which questioned Aristotle, treating the world as a machine. Grosseteste challenged Aristotle's claim that the stars were eternal and divine. He claimed the heavens were made of the elements rather than an etherial substance, and denied the existence of Aristotle's "prime mover." [Nebelsick, p. 129]
Roger Bacon (c. 1214-1294) of Oxford, a Franciscan, was a student of Grosseteste and a contemporary of Aquinas. He was familiar with the astronomical and astrological writings of the Greek philosophers and the Church Fathers. He regarded nature as part of God's revelation of himself, and wrote: "all wisdom is constituted with a view to the discovery of salvation for the human race." [Nebelsick, p. 132] Thus he thought the study of science was profitable for the Christian. He admonished scholars of his time to make a thorough study of science and to give up a literal interpretation of the Bible, pointing out several passages in obvious contradiction to known facts. This antagonized the clergy and he was jailed for ten years. His writings were forgotten.
Thomas Aquinas (1225-1274), at Paris, reconciled Aristotle's philosophy to Christian theology in a grand synthesis, apparently supported by biblical authority, contained in Commentary on Aristotle's On the Heavens, and On the Eternity of the World. While he accepted Aristotle's cosmology, he denied the heavens were eternal, on the basis of the creation account in Genesis. In his Summa Theologica, Aquinas considers the events of each of the days of creation week in detail. He encounters little difficulty reconciling the cosmology of Genesis 1 with Aristotle, who he refers to as the Philosopher. In Summa Theologica I, 68, 4, Aquinas writes:
In order, then, to understand the distinction of heavens, it must be borne in mind that Scripture speaks of heaven in a threefold sense. Sometimes it uses the word in its proper and natural meaning, when it denotes that body on high which is luminous actually or potentially, and incorruptible by nature. In this body there are three heavens; the first is the empyrean, which is wholly luminous; the second is the aqueous or crystalline, wholly transparent; and the third is called the starry heaven, in part transparent, and in part actually luminous, and divided into eight spheres. One of these is the sphere of the fixed stars; the other seven, which may be called the seven heavens, are the spheres of the planets.
Dante Alighieri (1265-1321) popularized Aquinas in his Il Convito and The Divine Comedy. He also depended on a work by Alfraganus of Baghdad (ca. 840), one of the successors of Ptolemy, Elements of Astronomy and Chronology, a greatly simplified version of Ptolemy's Almagest. Dante's cosmology included Aristotle's Primum Mobile as the ninth sphere, and he added the Empyrean, the dwelling place of God, and "beatified spirits," as the tenth. This tenth sphere was thought to be immovable, like the earth. Orr wrote:
That Dante should believe the spheres to exist as actual entities was inevitable, for his principal authorities, Greek, Arab, and Christian, all taught this. And there is abundant evidence that he did think of them thus... They are transparent, one sphere not obstructing the light from another; and composed of ether, "questo etera tondo." They have a certain thickness, and would be visible if near enough, for Dante speaks of the inner margin of the Primum Mobile, and says that it was too far above him for him to have seen it yet, when he was in the Star Sphere. He gives the order of the eight heavens as in Ptolemy, and adds the ninth, which is only perceived by the diurnal movement of which it is the cause; and it is called by many the Crystalline, that is, the diaphanous or completely transparent Heaven... To these nine spheres of the astronomers, the Catholic Church, "which cannot lie," adds a tenth, the Empyrean Heaven, which means the heaven of flame or light, and is the abode of the blessed spirits and of God Himself.
He made Purgatory a mountain in the midst of a great ocean, antipodal to Jerusalem, with the earthly Paradise on top. He referred to the interior of the earth as an Inferno, with various levels. He compared the "nobility" of celestial spheres with different branches of science and philosophy.
[See Dante library.]
Belgian Cardinal Nicholas of Cusa (1401-1464) in his On Learned Ignorance speculated that the universe was infinite and therefore could not have a center, and hence the earth could not be at the center of the universe.
According to Italian philosopher Johannes Pico della Mirandola (1463-1494), Moses wrote figuratively about the structure of the universe in Genesis. Pico suggested the "waters above the firmament" were symbolic of the crystalline heaven beyond the sphere of the stars. He wrote: "Between the 8th sphere and the empyrean is what Moses symbolically calls 'the waters,' the 9th sphere, the 'crystalline heaven.' Above that sphere the Spirit 'brooded' (Gen. 1:2), i.e. imparted life-giving light to the lower spheres. The terms 'water' and 'earth' in the first chapter of Genesis denote the 9th sphere and the other spheres of the astronomers." [Hooykaas, p. 32]
The concentric structure of the universe was extended not only up to the heavens but downwards, towards the earth's center as well. The center of the earth was considered to be the location of hell as being the furthest possible from heaven. One such proposal about the nature of the earth's interior is that of Giovanni Gallucio. Kelly wrote:
Giovanni Paolo Gallucio in 1558 offered a novel structure for the interior of the earth in an otherwise conservative world system. Underneath Gallucio's region of earth and water, the part of the earth in which metals, earthquakes, and other surface or near-surface events occurred, was Limbo, followed by Purgatory, and then, in succession, the regions for the fighters, the vainglorious, the gluttonous, the oath takers, the angry, the covetous, the proud, the traitors, and finally, at the center, Lucifer. The explanation given for this arrangement was that the inhabitants of these regions were to be as far from God as possible, and the center of the earth was the place the greatest distance from the empyrean.
Robert Recorde (1510-1558) popularized astronomical knowledge in The Castle of Knowledge, which mentioned the Copernican theory but discredited it. He criticised and corrected statements by ancient authorities. Recorde established the custom of presenting learned scientific works in the vernacular tongue.
This brief survey of cosmological thought until the Copernican revolution reveals the overwhelming attraction which a comprehensive system of explanation of the natural phenomena of the heavens had on the mind of man. Aristotle offered such a system, and his system, imposed on the biblical narrative, produced a modified world-picture, one that was complicated by the upper waters. It was this modified cosmology that deeply influenced Christian thought. Dicks wrote [Dicks, p. 217-218]:
Aristotle himself can hardly be blamed for the fact that some of the main features of his universe (e.g. the unmoved movers, which St. Thomas Aquinas interpreted as angels, and the notion of concentric shells) lasted nearly 2,000 years, being incorporated in different forms in the religious beliefs of Mohammedans, Jews, and Christians as official dogma which it was dangerous to question. Moreover, it was not what one might call 'pure' Aristotlean doctrine that appealed to later thinkers that was to prove such a potent influence on Medieval thought, but a composite mixture made up of elements from Plato (especially from the Timaeus), Aristotle himself (in De Caelo and Meteorologica) and the Neo-Planonists (especially Proclus and Plotinus). This blend of doctrines was particularly congenial to the Arabic philosophers such as Avicenna (tenth and eleventh century) and Averroes (twelfth century), who passed it on to the Latin West. If an explanation is needed for the relative stagnation of science during the Middle Ages, it is to be found in this curious amalgum of ideas butressed by the authoritarianism of religious dogma.
The Copernican revolution appeared to the theologians as not only a rejection of Aristotle and the Ptolemaic system, but because the scriptures referred to the rigid heavenly firmament and the upper waters, it seemed to be in contradiction to the Bible as well.
Neugebauer, O. 1949. The astronomy of Maimonides and its sources. Hebrew Union College Annual 22:322-363. (See p. 336.) Reprinted in: Neugebauer, O. 1983. Astronomy and History: Selected Essays. Springer-Verlag p. 382-423.