This mendacious activity of the Church caused a natural rejection in all intelligent and honest people. A.Arnu  wrote the following: “… Hate towards the clergy reached such a level that even the word priest was considered a curse”. Here and there would appear “protestant” Christian communities. The largest one was the Lutheran movement that originated in Germany. At that time the “aggressive” people defined a “heretic” as everyone who was discontented with the existing order, i.e. all those who deviated from the “true” “Apostolic” Church. A merciless war was declared on them.
In order to exterminate all their opponents, the “aggressive” established a “Christian police” in the form of a special monastic order of the “holy inquisitors” headed by “saint” Dominic. The task of those “monks” was the elimination of all “heresies”. Later on, Minorites (monks of the Franciscan order) and Jesuits joined the ranks of the “holy inquisitors” [15,37-38,49,53].
The “chief theologian” of Catholicism at the time — Thomas Aquinas — declared that “Heresy is the sin, the guilty of which must be not only excommunicated but also taken out of the world by death”. And the Pope ratified this postulate with his encyclical .
The most popular means of struggle against “heretics” was burning them alive. But since such executions had to look like “legitimate” acts, inquisitors made all efforts to “knock” confessions out of their victims. For this they always used torture. The most popular of them were the following: burning of the limbs in fire, pouring water into the lungs; there was also the “rack” — the torture technique of dislocation of both shoulder joints simultaneously; while the victim’s body was still hanging by the hands it was stretched down by a load attached to the legs or with a special winch. The tortures were conducted in the torture chambers that existed in monasteries.
This is how A.Arnu  describes the manner in which the Inquisition worked in Spain:
All people — boys from 14 and girls from 12 years old — had to give an oath that they would prosecute “heretics”; in case they refused they were going to be treated as suspected “heretics”, i.e. tortured and burnt alive.
All property of “heretics” would get confiscated for benefit of the king and the inquisitors, their children disinherited.
Sentence would also get passed on those “heretics” who were already dead by the time. Their remains would get exhumed and burnt. This was done with the purpose of confiscating the property from their heirs.
“Monks”-inquisitors were immune from the jurisdiction and control of the temporal authorities.
Among the grounds for sentencing a person for heresy were the following: information or rumors that someone incorrectly understands the omnipotence of God, evokes spirits, hides heretics, or sympathizes with them. Secular officials who refused to implicitly obey the demands of the inquisitors would also get cursed and persecuted by the Inquisition.
People were supposed to inform the Inquisition of heretics. The proof of their guilt was not required. Testimonies from the most wretched individuals would get accepted, and their “testimonies” would be enough to throw any person in the fire. So, everyone who was at odds with someone or lent money to someone who did not want to pay them back — would get reported to the Inquisition as a heretic. As a result, the creditors were murdered; all their property confiscated. Their families were made destitute. Any protest or expressed discontent would get interpreted as sympathizing with “heresy” and would serve as a ground for arrest, tortures, and execution. “… Spying and denouncing were considered a Christian’s primary duty and had to be the major occupation of the crowd of ignorant fanatics and mean individuals…” .
There were many cases when people would get burnt only for wearing a clean shirt on Saturday: that was enough to accuse a person of being a follower of Judaism .
“Laymen” would get burnt even for reading the Bible: since the only ones who had the right to read it were members of the clergy — since “ordinary people” could “misunderstand” it… .
Dominican and Franciscan “monks” were so carried away with their inquisitorial activity that they would start prosecuting “monks”-inquisitors who belonged to the contending order, when they lacked victims for tortures and burning .
It was not that “heretics” were burnt in secret: in the woods, on special isolated territories. No! They were burnt in public — on squares, with specially organized festive church ceremonies! Often those burnings were dated for certain important events or celebrations.
With time, none of the events like that were conducted without the burning of people. The more solemn the celebration was, the more victims had to be burnt during the event. Usually their number was measured by hundreds. Once there was a record: 950 people died in fire! .
Although, an embarrassment occurred one day. That did not happen during some inauguration… No! That nonsense took place during canonization of Dominic himself! Pompous festivities already began when it turned out that the organizers had overlooked preparing victims for the burning… Then, the woman who had been suspected of heresy was hastily found. When inquisitors came to her place she was already near death. Then they took the dying woman out to the square on a stretcher and threw her into a fire .
… But one should not think that there were no true Christians in Europe at that time. There were! They were among the “heretics”, who for the sake of the true Path to God were willing to resist those devil-like “monks”, which at the time represented the primary force of the Catholic Church. History preserved the names of some great spiritual heroes, true Christians, who preferred death in fire to betrayal of the true faith. Some of them, even when being burnt, would support and hearten their fellows who suddenly gave in to fear.
One of those heroes was Giordano Bruno, who had been tortured for four years! This is what he told his executioners in response to the sentence: “Perhaps you pronounce this sentence against me with greater fear than I receive it!” .
Spain was hit the hardest by the Inquisition. During the time the Inquisition prevailed, it lost half of its population (burnt, escaped, and expelled), including all Semites (Jews and Arabs) who lived on its territory, as well as a great number of Native Americans in its American colonies.
Native Americans, among other ways, were treated as follows: Spaniards would gather them in one place, read to them instructions as to how they were supposed to conduct themselves in order to be considered good Christians — instructions that were in Spanish that Native Americans could not understand, of course. And then they would torture and burn all those who did not comply with those rules [37-38].