In Mark Helprin's "A Soldier of the Great War," the quote illustrates the idea that a profession can become all-consuming, resembling a great snake that wraps around an individual. This metaphor reflects the struggle of being entrapped by one's career, suggesting that it dictates the individual's thoughts and actions, leaving little room for other experiences.

The passage further emphasizes how this entrapment leads to a loss of youthful freedom and vitality. The speaker indicates that even during everyday activities, like walking through a city, one's profession imposes a constraint that prevents deeper contemplation or enjoyment of life, highlighting the weight of professional obligations.