I inspired myself by thinking in imposing pope clothes, including the hat and the flashing arc on his head.
According to Persona 3, which uses the tarot topic to build the story:
"The Hierophant is a symbol of education, authority, conservatism, obedience to rules and relationship with the divine. The definition of a "hierophant" is a person who interprets sacred mysteries or esoteric principles, and the term was originally used to name ancient Greek priests who did so."