So, your "dedicated anarchist" author was baptized as a Southern Baptist years before he poped. How is it, then, that he can convert to Roman Catholicism and his Southern Baptist baptism isn't binding on him? Baptized a Southern Baptist, always a Southern Baptist...isn't that what infant baptized Roman Catholics who leave are constantly told here? The only difference is he at least gave his consent to be baptized as a statement of his faith rather than it being done to him while he was but a little baby.
Your answer proves my point. Baptism is not a branding. It’s a ritual that washes away original sin. Those whom John the Baptist baptized were free to renounce the commandments either as adults or as adolescents. You and I know there are many Catholics and Protestants who turn out to be agnostics and atheists. Indeed this is true for Jews as well as other faiths too.