The nineteenth century was a time of great expansion in the United States, and by extension the churches and Christian movements. Demand for new preachers and ministers burgeoned, that the many new communities founded had God in the hearts and minds of their inhabitants. Having lived in what was an environment of upheaval, Brooks felt it appropriate to pass on the wisdom and advice to prospective new ministers looking to found or join parishes around the country.
Making and delivering fine sermons, the messages of which stay with the congregation, is at the heart of what a good minister does. Yet the work is not confined to merely this; the preacher must be a support to the communal and spiritual life of his locality, that his congregation be kept in good health, and that their souls be shepherded toward a life of virtue and good conduct. The preacher must also turn his attention inward: his character must be examined for flaws or bad habits, with virtues cultivated, that he stand as a model for the wider community.