To him, as to me before I read The Name of the Rose by Umberto Eco, the Inquisition, supposedly a Roman and Spanish thing, mainly, was an obstacle to Roman Catholic conversion.
He obviously thought the Inquisition bad at least back when he wrote his Answer to Professor Haldane, not published in his lifetime, not finished, but published posthumously by Walter Hooper. He wrote he did not know why C. S. Lewis left the essay unfinished or why last page is missing.
My guess is, he returned to the example of the Inquisition, then thought he ought to consult a Catholic friend to whom the Inquisition was no problem about being Catholic. Like the very Catholic very good friend John Ronald Reuel Tolkien. He got an answer and saw he had no real case. Because Inquisitors like Bernard Guy and St Robert Bellarmine, and in some measure maybe even Torquemada, were far from what English opinion painted it out to be.
C. S. Lewis honoured Tyndale as a saint. And Tyndale was burned under Mary I Tudor. Now, was she acting on behalf of Rome or of Spain? As far as Belloc is concerned, her Spanish husband King Philip of Spain did not want it. But he allowed it since she was reigning Queen and he just Prince Consort of England and Ireland (Scotland was as yet a separate Kingdom, under Mary Queen of Scots). So, why was she doing it?
The Watchtower Society in its Readers Digest type of publication Awake! had an article about John Foxe, the martyrologist of Protestantism, first mainly of English Lollards and those inspired, like himself, by Continental Protestants - then of Western Anticatholics from 1000 to his own era. First edition, Latin, published on Continent, in Strassburg, had 212 pages. His final English edition had 2300 pages, with some 150 illustrations.
But the article writer in Awake! made it clear that the law against the Lollards was an English law, passed by the Parliament in 1401.
So, Tyndale was indeed burned by a tyranny with very supreme and not so pragmatic reasons for power - but that kind of Inquisitor came from England and from Parliament, 1401 - not from the Pope, except indirectly. It is probable that the bishop Cauchon of Beauvais, considering himself as an English subject, may have acted under the law of 1401, and that that law placed no such restrictions on powers of torture as the really Popish Inquisition did. [Not quite, he used the English procedure only after checking with the University of Paris, B B L on French and English Inquisitions] It is certain that the English one was directed against the Lollards, and that burning St Joan of Arc may have been an act of paranoid or associative or guilt by association type lollardophobia. Rejecting Lollardism is one thing, but taking her for a Lollard was bad logic.
Lollards said war was never just under New Testament, except for the case that God declared it just by special revelation. St Joan of Arc did have a special revelation declaring her war on the English in France just, but she did not believe that that was the only possibility for a Christian to take up arms, as the Lollards did.
There is also the doctrine of "just war" (just as in justified, not as in holy by itself), as exposed by Sts Augustine and Thomas Aquinas and practised against the Teutonic Order by Alexander Nevski and by Poles and Lithuanians at Grunwald.
It is related to doctrines of just self-defence - including in some cases against apparently legal state power. I say in some cases, because most of the time an apparently legal state power is at the same time legitimate and really legal state power. I say against apparently legal state power, because when state power exceeds its legitimate limits, whether against a nation invading it or against particular individuals or families invading their peaceful lives, it ceases to be legitimate and that is the occasion when it can legitimately be opposed by just self defense. That is no matter of private special revelation, but of known Catholic doctrine.
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