Examine the Priest's actions and words after hearing the news of the pearl. What is his reaction? How do you know Kino doesn't trust him?

The priest hopes that he was involved with Kino's life enough for Kino to give him money. Kino would know that the priest has never done him or his people any favors: they are too poor.

"It came to the priest walking in his garden, and it put a thoughtful look in his eyes and a memory of certain repairs necessary to the church. He wondered what the pearl would be worth. And he wondered whether he had baptized Kino's baby, or married him for that matter."