What is an Interceder?

to act or interpose in behalf of someone in difficulty or trouble, as by pleading or petition: to intercede with the governor for a condemned man. to attempt to reconcile differences between two people or groups; mediate.

What is the difference between intercessor and advocate?

As nouns the difference between intercessor and advocate

is that intercessor is a person who intercedes; a mediator while advocate is someone whose job is to speak for someone's case in a court of law; a counsel.