Some Catholics insist that Galileo was condemned, not for his scientific views, but his theological views. Here for example, is Patrick Madrid:
Galileo confused revealed truths with scientific discoveries by saying that in the Bible "are found propositions which, when taken literally, are false; that Holy Writ out of regard for the incapacity of the people, expresses itself inexactly, even when treating of solemn dogmas; that in questions concerning natural things, philosophical [i.e., scientific] should avail more than sacred." Hence, we see that it was Galileo's perceived attack on theology (which is the unique domain of the Magisterium and not of scientists) that elicited the alarmed response from the Church.
Thomas Lessl takes a similar view: that Galileo’s scientific views were not the “real source of his ecclesiastical difficulties”
What, then, caused the row with the Church? The first thing to remember is that Galileo's heliocentric theory, although sternly opposed by theologians… wasn't the real source of his ecclesiastical difficulties. Rather, the cause of his persecution stemmed from a presumption to teach the sense in which certain Bible passages should be interpreted….
McAreavey, in a letter to The Guardian, also voices the view that Galileo’s
subsequent trial and house imprisonment was not for his scientific views but for his refusal to refrain from theological interpretations of scripture.
Madrid also quotes Rumble and Carty:
Galileo made the mistake of going outside the realm of science to invade the field of theology. He set himself up as an exegete of Scripture and thus brought upon himself the censures of lawful religious authorities.
That belief that the Church's dispute with Galileo was essentially theological, not scientific, is held by a significant number of Catholics (though of course by no means all). Is the belief true?
The issue of "interpretation of scripture"
Galileo was brought before the Inquisition because he was alleged to have claimed that the Copernican system was not merely a useful hypothesis, but literally true - an opinion the Holy Office had already commanded him to relinquish back in 1616.
What happened is this. To claim that the Copernican system is not just a useful hypothesis, but literally true, is, on the face of it, to contradict what the Bible has to say. See for example:
…tremble before him, all earth; yea, the world stands firm, never to be moved. 1 Chronicles 16:30
The Lord reigns; he is robbed in majesty; the lord is robbed, he is girded with strength. Yea, the world is established; it shall never be moved. Psalms 93:1
Say among the nations, "The Lord reigns! Yea, the world is established, it shall never be moved; he will judge the peoples with equity." Psalms 96:10
Also see Joshua 10:12-13, where Joshua commands the sun to “stand still” – which it does, which entails that it had been moving.
In claiming that his theory was literally true, then, Galileo would immediately be seen by many to be contradicting holy scripture.
Galileo was indeed accused of contradicting scripture by his enemies Colombe and Caccini.
Short of saying that, “Yes, The Bible is indeed in error”, Galileo was then left with no choice but to say that these and other Biblical passages would, then, have to be interpreted differently.
Which is what he did say.
This certainly did upset the Church – particularly as it was believed Galileo had failed to supply any demonstrative proof of his scientific theory at that time (he had no proof, in fact).
Some theologians (e.g. Cardinal Bellarmine) were prepared to accept that scripture must indeed be reinterpreted if it could be proved that the Earth moved and the sun didn’t.
But here was Galileo claiming scripture must be reinterpreted, yet he could supply no proof! So now he's in trouble!
Does all this, then, vindicate the claims of Madrid, MacAreavey and Lessl?
Madrid and MacAreavey
Now let’s return to MacAreavey, who says,
[Galileo’s] subsequent trial and house imprisonment was not for his scientific views but for his refusal to refrain from theological interpretations of scripture.
Madrid concurs. Now it is true that Galileo’s claim that scripture would have to be understood differently did indeed upset the Church, and certainly was an issue at his trial.
But of course, the only way Galileo could cease to make the claim that scripture would have to be interpreted differently would be to either (i) insist the Bible was just false, period, or (ii) cease asserting his scientific theory was literally true.
So the Church certainly was demanding that Galileo cease claiming his scientific theory was literally true.
It is clear, then, that Galileo’s scientific claims were not irrelevant to his trial. Far from it – they were pivotal.
On that issue, MacAreavey and Madrid are just wrong.
However – we might still debate to what extent it was Galileo's scientific views, or just his theological views, that were fundamentally at issue.Which brings us back to Lessl...
As we saw above, Lessl says:
Galileo's heliocentric theory, although sternly opposed by theologians… wasn't the real source of his ecclesiastical difficulties. Rather, the cause of his persecution stemmed from a presumption to teach the sense in which certain Bible passages should be interpreted….
Lessl makes the dispute primarily theological, not scientific. Is that fair?
I don't think so.
The Church’s position was this: that scientists could not - on pain of imprisonment, torture or even death - express a scientific belief contrary to what scripture appeared to say unless they could provide proof that the belief was true (in which case, scripture would have to be “reinterpreted”).
It is this position that lies at the root of Galileo’s difficulties with the Church.
It is a position on what scientific beliefs may be expressed.
Perhaps you're still tempted to think Galileo's trial primarily concerned Galileo's view that scripture must be reinterpreted?
Then consider this analogy. Suppose a mad dictator, Fred, decrees the Earth is flat, and then dies. Fred's totalitarian regime continues on without him, however, imposing his beliefs upon its citizens. But then a scientist under the regime dares to voice the view that the Earth is not flat, but round. The scientist is arrested, tried and imprisoned for life. Accused by other nations of suppressing scientific theories, the regime responds by saying that the prisoner was (primarily!) prosecuted not for his scientific views - oh no, no, no! - but for his Freddist views - in particular his suggestion that Fred must either be wrong, or else reinterpreted.
We would be astonished at their chutzpah, would we not?