Answer:
His theories went against church teachings.
Explanation:
Originally, the church believed in a theory that the Earth was in the center of the universe, developed by Aristotle. However, Galileo developed or built upon (I can't remember which one) that stated the sun was in the center of the universe, based off of science at the time. The church did not like this, as it was going against their teaching, and wanted to prevent its spread.
Hope this helped!
