The novel's tone is determined by Lauren's attitude and reaction toward what unfolds in her environment, since she narrates the story via her journal entires. Lauren responds to her world with urgency but also hopelessness for any chance of true prosperity on Earth. She also expresses frustration (toward the stubbornness of the people around her who do not want to let go of old ways of the world), and informative (reporting to the reader the tangible events and situations that she experiences while also documenting her though process for the development of Earthseed).
It is crucial to Lauren that she and the people around her recognize how greatly their world has and will continue to fail them. The government has clearly lost control in maintaining law and order, leaving people to fend for themselves amid rampant crime and social inequality. The climate crisis also continues, while a new drug, pyro, makes the spread of fire even more prominent and dangerous. These conditions inspire within Lauren a sense of urgency to move and change as quickly as possible, rather than reconnecting with old values and environments that no longer seem to serve the people of Earth. Together, these conditions inspire Lauren to prepare for disaster and move away from her gated community, in hopes of establishing new modes of relation from the ideology of Earthseed.
Lauren's lack of hope in life on Earth contrasts directly with the tenets of Earthseed, which insist on life among the stars as humanity's salvation. Lauren believes that she sees and speaks to a truth that those around her are unable to see. This is largely due to their being blinded by the constant destruction that surrounds them. Lauren is thus akin to a messiah or prophet who will guide her followers to a new and better life. Urgency and frustration, then, as well as the claim to a greater truth, are fitting for her role as a religious leader.