Was Galileo really a heretic? Reason and quote to support your reason

He was a heretic according to the Church which was the ultimate law behind all questions regarding the earth. Although his teachings were accurate, they went against the Church so naturally they were heresy since anything that was against the Church teachings was heresy. Of course, nowadays we wouldn't label him as a heretic, but at the time when he did it he was indeed spreading heresy, even though he was speaking the truth.