It is this.

You must give up all thoughts, all hopes, all designs, of ever winning Gertrude Forrest for your wife." "And if I refuse ?" "If you refuse, I shall have to make you do what I would rather you would do willingly.

Think as you will, but she can never be yours.

I do not mind telling you now, for you dare not speak.

I have marked her for my own; and, mark you, she must be mine.