In The Shakespeare Stealer, what does Nick mean when he says, "I've no fear of blows. They're braver than words."

Nick is asserting that attack through words is weak and
cowardly; one can say much but it is often one's actions which are judged. He feels it
is more noble to act on one's emotions with physicality rather than react with taunts
and empty threats. He is of course trying to save face by fighting valiantly with a foe
who is indeed a match for him, but is a woman.

The context
of the statement is that in Chapter 21 it is revealed that the fight Nick had with
Julian ended with him discovering that 'Julian' is a girl. Nick had taken himself to the
ale-house to console his wounded pride. He is fired up when Sander reveals
publicly 'Julian's' gender and he is then ridiculed. Nick finds it easier to deal with
physical defeat than he does the mental defeat of being outwitted by a mere
woman.