Final answer:
Liberty of conscience was defended by Roger Williams because he considered it a divine gift, aligning with Enlightenment principles and influencing the separation of church and state in the U.S. Constitution.
Step-by-step explanation:
Roger Williams defended liberty of conscience on the grounds that conscience was a divine gift. This belief holds that individuals possess an inherent freedom to believe and practice their religion without compulsion or interference from the government. The idea finds its roots in the Enlightenment and in the thoughts of philosophers like John Locke, who argued that government should not have authority over individual conscience, as rational beings could not cede such personal jurisdiction to any external authority. This concept forms a basis for religious freedom and the separation of church and state, philosophies which greatly influenced the Founding Fathers and the drafting of the United States Constitution, which later included a Bill of Rights to protect such liberties.