Why was Galileo sentenced to life in prison?

Answer 1

Because he asked to go there. After Galileo put forth the idea that the earth revolved around the sun, there was a strong reaction from the Church. Up until the time of Galileo, Aristotle's idea of geocentrism, the idea that the sun and other heavenly bodies revolved around the earth, was firmly held. It was seen as blasphemy to offer that heliocentrism, the idea that the sun was the center around which the earth and other planets revolved, was the manner in which the heavens worked. How dare he. Galileo was taken before Church authorities and told to abjure regarding heliocentrism (which essentially means "cease and desist") and that he was going to prison and that none of his work would be allowed to be published. The prison sentence was reduced to house arrest, and arrangements were made for Galileo to stay with the Grand Duke near the Trinita dei Monti. He remained there for a short while but requested to be sent to stay with the Archbishop of Siena, Ascanio Piccolomini, with whom he was friends. This request was granted, and he spent time there before being permitted to return to Arcetri (the location of his villa), near Florence. There he remained for the rest of his days. Wikipedia has additional information. Need a link? You got it.

Answer 2

He shot someone