He is cast in the image of the pope in this deck but the word Hierophant is actually Greek and means the high priest of the Eleusinian mysteries. The Elusian mysteries were initiations into the cult of Persephone and Demeter.
So this card is actually combining the leader of the Catholic Church with a pagan cult dedicated to two goddesses.
I can see why that might ruffle some feathers.
There are two crossed keys and those remind us that knowledge is the key that opens many doors.
He has people bowing before him. Why is that? Is it because he is a master from whom they wish to learn or is it because they have been lead to believe that through him is the only way to achieve what they desire.
You either must accept your niche within his structure or you may choose to rebel.
It can indicate that a very strict niche is hindering rather than helping your querent.
This card can indicate a marriage when you see it with justice and lovers. Right side up it foretells a traditional marriage with a focus on cultural and or religious rules and standards.
Sometimes the Hierophant is telling us to study, to go to University or College. To gain some kind of formal training or certificate.
He can be a person in your life who is a teacher, religious leader or a boss who has strict rules and hierarchy.
He can also represent any very structured institution. If you see him with the Chariot, Knight of swords or any other warrior focused cards that can mean the military.
This is a good card to pay attention to if it comes up inverted because the meaning is quite straight forward. So if it is inverted that can either indicate that there is a total lack of structure in the life of the querent and that more is badly needed, or alternatively it can show a positive free flowing nature with a lack of structure that feeds the soul and allows the querent to flourish.