The correct answer to this open question is the following.
Considering what I know of Roger Williams — that he was a Puritan with strong beliefs but also went against church leaders —I think the official church of Rhode Island was a place to worship God, but enough criteria to respect other religious systems because Williams supported religious freedom and always expressed tolerance to different religious points of view. Roger Williams was the founder of Rhode Island, and from the beginning, he worked for the separation of state and religious issues. When he publicly told that he was against the confiscation of land that belonged to Native American Indians, the people from the colony rejected his ideas and Williams had to leave Massachusetts Bay Colony and with a group of supported he traveled to modern-day Rhode Island, where he founded the Baptist Church of Rhode Island. A place where religious tolerance allowed many forms of though.