This is still religious persecution, and they are still martyrs, but it’s significantly different from executing someone for their views on the Real Presence or justification by faith or so on.
Actually, it’s not. Submitting to the Pope is a religious requirement for Catholics, it’s a doctrine of the faith just as much as the Real Presence. They were not raising armies against the English monarchy, they were simply making the point that the Church is headed by the Pope, not the King of England. If submitting to the Pope was an act of treason, why wasn’t it considered treasonous prior to Henry VIII spliting with the Church over doctrine? Why did common, everyday assumptions suddenly become treason when the nation became Protestant?
The reason heretics were considered enemies of the state in Aquinas’ time was precisely because the state’s authority was said to come from God, not from man. To reject God was, de facto, to reject the state. In fact, it usually worked out to be much more than just mental rejection, but actual outright rebellion, as can be seen in the Albigensian Heresy. This is no different than what happened in England when Catholics refused to abandon the Pope as directed by the monarchy; they were staying loyal to their faith, and were persecuted for it. To reduce it to “mere politics” is to utterly ignore the fundamentals of the Catholic faith.
The comparison Aquinas makes is with forgery, not treason, and it’s a comparison, not an identification.
You don’t seem to understand the implications of forgery of money, then. Money, in those days as well as in the modern U.S., was minted under government authority, and was valued according to government fiat. To forge it was to commit treason against the monarchy by usurping its authority. When you forge money, you are essentially saying “I am the king, and I say this money is good”. That
is treason; kings weren’t simply putting people to death for wanting to better their material lives.
But (precisely because of the vital importance of true religion for civic order) the state had the responsibility of punishing those who offended against the Church.
I’m afraid this completely ignores the European understanding of monarchy, which is often summed up under the term “Divine Right of Kings”. A king, in the European mind, was someone vested with temporal authority by God Himself. The Holy Roman Emperor (Eastern France and Germany) was even crowned by the Pope in person; an attack on the authority of Church was* by definition* an attack on the king, since the king was legitimized by Church recognition. Heresy and forgery of money (minting money was done only by the authority of the crown) were both then seen as undermining the rule of the monarchy, and punishable by death as treason. After all, you can’t very well be a loyal subject to a king crowned by the authority of the Pope if you reject the very authority of said Pope.
The Church did not put anyone to death because the Church did not believe that it was allowed to wield the sword of temporal power on its own behalf. Exercising the death penalty was recognized to be incompatible with the nature of the Church. The practice of “relaxing” heretics was of course a flimsy bit of hypocrisy. But hypocrisy is often the last vestige of an uncomfortable principle–so here.
And had it not been considered treason by the temporal powers, the heretics likely never would have been put to death at all, as can be seen in all countries in which the ruling power does not derive its authority from the Church. In those days, the state simply recognized the spiritual authority of the Church to determine heresy, and the Church simply recognized the temporal authority of the government to protect itself from threats. In those times, in Europe, heresy nicely overlapped into both realms of authority. In times when temporal authority was not so closely connected with the Church, heretics were simply outcast, as can be seen in the time of Paul’s writings to Corinth, and the period between the Apostles and the conversion of Rome.
Basically all Aquinas was arguing for was moral consistancy. If a person who forges money is considered a traitor to the crown, and a danger to society by virtue of usurping the crown’s authority, than how much more is a traitor to the faith, which
gives the crown that authority, a threat?
In places and ages in which the authority of the government is not based on Church approval, or when treason is not considered punishable by death, Aquinas’ point is irrelevant. That’s why his point is
conditional, and his argument is hedged in very conditional terms such as forgery being treason.