Before you go and leave fundamentalism, or if there is some other entity or cradle belief from which you are considering departing, consider the advice of Jonathan Edwards, who wrote in his personal diary,

If ever I am inclined to turn to the opinion of any other sect: Resolved beside the most deliberate consideration, earnest prayer, etc, privately to desire all the help that can possibly be afforded me from some of the most judicious men in the country, together with the prayers of wise and holy men, however strongly persuaded I may seem to be that I am in the right. (May 21, 1725)