There is a characteristic underlying irony of tone in this poem that expresses Crane's opinion on the illusions held by men: If they believe in God [notice Crane's use of the small letter g] in order to survive in an indifferent universe--a belief which Naturalism does not hold--let people perceive these illusions at times. For, in this poem, the subjectivity of people is presented in their failure to perceive that the god of their imagination is anything but "redoutable."
Certainly, too, the lack of free will is metaphorically presented by the man's futile struggle as he "bit madly at the feet of the god," and yet in their limited perception, the deterministic people condemn the struggling man as "wicked" rather than respond to his screams. Moreover, in their religious pretensions, they praise the god,
"Ah, what a wicked man!" ...
"Ah, what a redoubtable god!"
Indeed, Stephen Crane's poem illustrates his skepticism and pervading pessimism about the condition of man whose inner reality often does not match that which truly exists. Herein lies the irony: How can man exercise a free will when his reality is subjective and he is, ultimately helpless in this illusory world?