During the Renaissance, the power of the Church was called into question by a number of deviations on the part of the religious authorities. It was also during this transitional period that Christianity underwent considerable change and split.

Martin Luther publicly burning a religious document
Life of Martin Luther and heroes of the reformation!, H. Brückner, Library of Congress LC-DIG-pga-00297. Domaine public.
Source : Library of Congress
While in the Middle Ages no one dared question the actions of certain members of the Christian clergy, many humanists, and even some religious, did so during the Renaissance. The Church was criticised for putting more effort into displaying its superiority than into genuinely helping the faithful. In fact, several behaviours of the religious authorities were called into question.
Among other things, the sale of indulgences is the most criticised element. Under this practice, the faithful can buy forgiveness and erase their sins before God in exchange for money given to a member of the clergy. The sale of indulgences is contrary to the very foundations of the Catholic religion, a religion in which forgiveness is an important value and is supposed to be free.
Other behaviours heavily criticised by intellectuals included failure to respect vows and simony (selling or buying spiritual goods or positions within the Church).

The image shows a member of the Catholic Church selling indulgences.
A Question to a Mintmaker, Jörg Breu the Elder, vers 1530. Domaine public.
Source : Pvasiliadis, Wikimedia Commons
At the time, people who wanted to join the Christian clergy promised to respect certain vows. For example, they took the vows of chastity and celibacy. However, many did not respect these vows, as it was not uncommon for priests to have families (wives and children). Members of the clergy also took a vow of poverty. On the other hand, many of them accumulated enormous fortunes. These examples explain the criticism of the vows of the clerical authorities, which were less and less respected during the Renaissance.

Representation of the wealth of the clergy
St Lawrence Distributing Alms (détail), Fra Angelico, entre 1447 et 1450, Musées du Vatican. Domaine public
Source : Sailko, Wikimedia Commons
Simony was another criticism levelled at the Christian Church of the time. It occurred when a member of the clergy demanded money in exchange for a sacrament. This practice goes against the basic values of Christianity, as the sacraments are supposed to be free.

Abbot practising simony
Source : Racconish, Wikimedia Commons
As the behaviour of the Christian Church was deemed inadequate, some humanists began to revolt socially. Such was the case with Martin Luther (1483-1546), the father of the Protestant movement. The fact that the Church was selling indulgences was the last straw for Luther. In 1517, he wrote a document entitled the 95 theses in which he criticised the sale of indulgences and stated his desire to reform the Church. Despite being excommunicated by the Pope in 1520, Luther continued his rebellion by translating religious texts into the language of the people so that they could be read and understood by all. He created his own church, the Lutheran Church. Protestantism was thus born.

Martin Luther posting his 95 theses
Luther hammers his 95 theses to the door, Ferdinand Pauwels, 1872, Fondation Wartburg Eisenach. Domaine public
Source : Lomojo, Wikimedia Commons
Following the reformation initiated by Martin Luther, several Protestant churches came into being. These included the Anglican Church and the Calvinist Church. Although all these churches are different, they share common values: equality of membership, faith and accessibility.
Catholics | Protestants | |
Who should we pray to? |
God, Mary, the saints and Jesus |
God and Jesus |
How do you get to heaven? |
Through prayer and works (gifts to the Church) |
Through prayer |
Who's in charge? |
Power is hierarchical (pope, bishop, priests). |
Power is equal between believers and pastors can marry. |
Who has access to the Bible? |
The Bible is in Latin and only certain members can interpret it. |
The Bible is translated into the language of the people and all believers can read it. |
What are the sacraments? | Baptism, Eucharist, Confirmation, Marriage, Extreme Unction, Ordination and Penance | Baptism and communion |
Of course, it was Martin Luther (1483-1546) who founded the Lutheran Church. This is considered to be the first Protestant Church. The differences with the Catholic Church were aimed at bringing believers closer to God, simplifying practice and dissociating themselves from the authority of the Pope. To this end, Luther wanted the mass and religious texts to be translated into the language of the people. He also withdrew the cult of the Virgin Mary. Finally, he gave less power to the celebrants of the Mass.

Martin Luther
Martin Luther (détail), Lucas Cranach the Elder, 1529, Lutherstiege Museum. Domaine public
Source : Wow, Wikimedia Commons

Henry VIII
Portrait of Henry VIII of England, Hans Holbein le jeune, vers 1537, Musée national Thyssen-Bornemisza. Domaine public
Source : DcoetzeeBot, Wikimedia Commons
Henry VIII (1491-1547) was the founder of the Church of England. In the 16th century, while King of England, Henry VIII wished to divorce his wife, Catherine of Aragon, because she would not give him a son to succeed him. He therefore applied to the Pope of the time, Clement VII. When the Pope refused, Henry VIII decided to create his own church, which he called the Anglican Church. In this branch of Christianity, the Sovereign of England is the supreme religious leader, not the Pope.
Along with Martin Luther, Jean Calvin (1509-1564) was one of the first humanists to question the actions of the Christian Church. He also founded his own church, the Calvinist Church. In fact, John Calvin took up most of Luther's ideas, but added the notion of predestination, i.e. the fact that God had already chosen in advance who would join him in paradise.

Jean Calvin
The creation of all these new Protestant churches changed the religious map of Europe, making it more diverse. The presence of the first three Protestant churches is notable.

Map showing the different religions present in Europe around 1789
Note: English image coming soon!
After the fierce criticism of Martin Luther and others in the Protestant movement, the Catholic Church felt the need to react. It did so in two main ways. On the one hand, it tried to curb the spread of Protestantism in Europe by using radical means. On the other hand, it also had a real desire to improve and change its ways.
The religious authorities used various means to stop the spread of Protestantism in Europe. These included the Inquisition and the Index.
The Inquisition is a religious tribunal that condemns heresies, i.e. beliefs that are contrary to those of the Catholic religion. People found guilty of heresy, heretics, could be arrested, tortured and even executed. This court already existed during the Middle Ages, but it was strengthened following the advent of Protestantism.

Painting depicting the Inquisition
Saint Dominic Presiding over an Auto-da-fe, Pedro Berruguete, between 1493 and 1499 approximately, Prado Museum. Public domain
Source: GDK, Wikimedia Commons

Painting depicting the Inquisition
The Inquisition Tribunal, Francisco Goya, between 1812 and 1819, Royal Academy of Fine Arts, San Fernando. Public domain
Source: Adam Faanes, Wikimedia Commons
This list of books banned by the Catholic Church was introduced in 1559. According to Catholic belief, reading a book on the Index leads directly to hell. Of course, many of the works of the humanists of the time are included.

Title page of L'Index, 1564 edition
Source : Ajvol, Wikimedia Commons
The Catholic authorities created religious orders with the aim of spreading their faith. Members of the orders travelled throughout Europe and the world to convert non-Catholics and to win Protestants over to their beliefs. One of the most popular orders was the Society of Jesus.

A work representing the Catholic Church's desire to convert
Père Marquette, Wilhelm Lamprecht, 1869, Université Marquette. Domaine public
Source : Petfalcon, Wikimedia Commons
The Catholic clergy are not just taking radical measures to protect their religion. They also tried to improve. They met at the Council of Trent to discuss the changes that needed to be made.
It was the Pope of the time who convened a council in Trent, a town near Venice. The aim of the meeting was to discuss possible changes that could be made to the Catholic religion in order to improve it and prevent it from disappearing in favour of Protestantism. Among other things, it was decided to tighten discipline among the clergy and standardise the training of priests.

Réunion du concile de Trente
Le concile de Trente, artiste inconnu, fin 17e siècle, Musée diocésain tridentin. Domaine public
Source : Alesvp, Wikimedia Commons
Tous ces changements amorcés par l'Église catholique sont des conséquences directes de la Réforme mise en place par Martin Luther au 16e siècle.