If you really had a flock that needed preached at, then grow your own priests. Why keep hollering for someone to come do it for you, when you could just do it yourself? If you can't be bothered to do it, then why should someone else up-end their entire life and come do it for you?
As for the prophet being quiet, it actually worked for us most of the time. It made him mysterious, and kept him above the petty politics of the church. It kept his reputation clean. Then when he spoke, his opinion actually meant something. You knew he wasn't one of the people talking just to hear themselves talk. In this way, Mathurin was one of the most respected and powerful men on the island. Also, he usually answered private letters, and even initiated important conversations on his own. I found his play style to be both appropriate and brilliant. He played the holy prophet of the world's largest religion perfectly.
