Who was expelled from the Massachusetts Bay Colony for advocating new religious ideas?

The individual expelled from the Massachusetts Bay Colony for advocating new religious ideas is Roger Williams. He was a Puritan minister who challenged the established religious authorities and doctrines of the colony, arguing for a separation of church and state and advocating for the fair treatment of Native Americans. His beliefs were considered radical at the time, leading to his expulsion from the colony in 1636.

Williams went on to establish Providence Plantations, which became a refuge for those seeking religious freedom. His emphasis on individual conscience in religious matters and the right to worship freely had a lasting impact on the development of religious liberty in America.