If you don't want them to bend the knee, you can at least make them leave you alone.

[He throws the flower on the ground, and it begins to wilt as soon as it leaves Flagg's hand.]

How? With the same magic I use to change my face. Once you've learned how to change yourself, changing other things is simple. I've been studying magic for a long, long time.

[And then he holds out his hand, a burst of flame briefly appearing on his palm.]