Galileo was sentenced to house arrest where he remained for the final nine years of his life.
Galileo had visited Rome nearly two decades earlier in order to defend his belief that the Earth orbits the Sun rather than the other way round after complaints to the Inquisition had been raised in early 1615. Despite his attempt to prove that heliocentrism didn’t contradict the Bible, an Inquisitorial commission in 1616 unanimously declared it to be “formally heretical since it explicitly contradicts in many places the sense of Holy Scripture.”
At that time Galileo was ordered to “abandon completely... the opinion that the sun stands still at the center of the world and the earth moves”. However, he was permitted to discuss heliocentrism in theory. It was this that caused him problems when, in 1632, he published a new book called Dialogue Concerning the Two Chief World Systems. Although written with permission from the Inquisition and the Pope, the book implicitly defended heliocentrism. Therefore, argued the Inquisition, Galileo had broken the sentence passed down 16 years earlier and should be forced to recant and be imprisoned.
Nearly 400 years later, in 1992, Pope John Paul II issued a declaration that recognised and expressed regret at the way the Catholic Church had handled the so-called Galileo affair.
