The reformation began when this man posted the 95 theses

The man being described is Martin Luther.

Martin Luther created the 95 theses based on his dissatisfaction with the Catholic Church. When he posted these 95 theses on October 31, 1517, he discussed several different factors about the Catholic Church that he felt were wrong, including:

1) The sale of indulgences - Indulgences was when a person was to be forgiven for committing a sin/crime by giving a certain amount of money to the church.

2) Religious posts (jobs) were often given to the person with the most money. Martin Luther felt that this was an awful way to conduct the church, as the person who had the most money did not always necessarily have the best intentions or the most knowledge about the religion.

3) The sermons given were usually in Latin - This was not the most popular language at this time so very few people understood Christianity as a whole. Instead, they relied on the priests interpretation as the only source of information.