What methods of studying the human body were used in the ancient and Middle Ages?

What methods of studying the human body were used in the ancient and Middle Ages? What difficulties was associated with the formation of the sciences of anatomy and physiology?

For the most part, they tried to study anatomy. But since this contradicted religion (autopsy was considered a sin among Christians), only later it was allowed to open the bodies of dead criminals. They also feared that doctors (and all those who treated people) were called magicians, whom the Inquisition tortured and burned.