Who is Jakan from Lamb: The Gospel According to Biff and what is their importance?

Jakan is a childhood bully that Maggie must marry due to a family arrangement. He grows up to become a wealthy and influential Pharisee. When Joshua returns, Jakan mounts a campaign to kill off the Mesiah, which is ironically exactly what Joshua wants. During Joshua's trial with the Jews, Jakan serves as the prosecutor.