the scarlet letter, symbol 33

Chapter 14

 “It is not granted me to pardon. I have no such power as thou tellest me of. My old faith, long forgotten, comes back to me, and explains all that we do, and all we suffer. By thy first step awry, thou didst plant the germ of evil; but, since that moment, it has all been a dark necessity. Ye that have wronged me are not sinful, save in a kind of typical illusion; neither am I fiend-like, who have snatched a fiend’s office from his hands. It is our fate. Let the black flower blossom as it may! Now go thy ways, and deal as thou wilt with yonder man.” 

I think what Roger Chillingworth means here is that when Hester comitted the adultery she already planted the evil (which is Pearl). He refers to her as the dark all the time, even though he is the evil one here actually. He keeps saying this was their fate, like it should convince Hester that he is not the bad one, it was just fate, what has happened is exactly what should have happened. In the end of this qote it's like he is giving up, he has done what he wants to do with Mr. Dimmesdale, and now they can do whatever they want. I don't think thats true, I think he will make sure Mr. Dimmesdale wil die.