Reference: Discoveries and Opinions of Galileo, tr. by Stillman Drake, Anchor Books, 1957
Galileo wrote a letter in 1615 “to the most serene Grand Duchess Christina.” In his second sentence Galileo notes his opponents were “academic philosophers” who held “physical notions” he contradicted. They were not ecclesiastical authorities as is so often claimed today. He asserts “they made the grave mistake of sprinkling” their “numerous writings” “with passages taken from places in the Bible which they had failed to understand properly, and which were ill suited to their purposes.” This sets up the focus of the letter on the proper relationship between what he later calls “mathematics” (which would be called physical science today).
He goes on to quote St. Augustine to the effect that “dubious points” should not be used to “conceive a prejudice” against something that may later be shown to be true of the Bible. He goes on to affirm he holds the Bible, theologians, and Church Councils “to be of supreme authority” as any good Catholic would but this is hedged by saying “when employed according to the usage of the holy Church.”
He holds “the sun to be situated motionless in the center of the revolution of the celestial orbs while the earth rotates on its axis and revolves about the sun.” Note the key issue is motion, not centricity, as Galileo accurately states it. The Ptolemaic position is that the earth is still and the sun in motion around it. He goes on to assert his opponents “have resolved to fabricate a shield for their fallacies out of the mantle of pretended religion and the authority of the Bible.”
Galileo states he is not asserting novel opinions but is the “restorer and confirmer” of the opinions of Copernicus who was a Catholic in good standing with the Church. Then he makes this statement about his opponents:
Contrary to the sense of the Bible and the intention of the holy Fathers, if I am not mistaken, they would extend such authorities until even in purely physical matters – where faith is not involved – they would have us altogether abandon reason and the evidence of our senses in favor of some biblical passage, though under the surface meaning of its words this passage may contain a different sense.
He notes about Copernicus —
For Copernicus never discusses matters of religion or faith, nor does he use arguments that depend in any way upon the authority of sacred writings which he might have interpreted erroneously. He stands always upon physical conclusions pertaining to the celestial motions, and deals with them by astronomical and geometrical demonstrations, founded primarily upon sense experiences and very exact observations. He did not ignore the Bible, but he knew very well that if his doctrine were proved, then it could not contradict the Scriptures when they were rightly understood.
So Galileo is confident that arguments that do not depend in any way upon the authority of sacred writings are not subject to questions about misinterpretation, and further, could not contradict the Scriptures when rightly understood. So these empirical arguments are more assured than the sacred writings because they bypass hermeneutical questions – first by being independent of sacred writings and then by reaching conclusions which will be reached from the sacred writings when they are properly interpreted. One might react, “who needs interpretation if you can know the right answer without the text?”