A statement which explains one of the motivations behind Manifest Destiny is the following passage from White-Jacket by Herman Melville:

We Americans are the peculiar, chosen people—the Israel of our time; we bear the ark of the liberties of the world. God has predestined, mankind expects, great things from our race; and great things we feel in our souls.

These words were written five years after the term "Manifest Destiny" was coined in a newspaper article by John O'Sullivan. Although Melville does not use the term, the attitude he expresses perfectly encapsulates the missionary zeal of Manifest Destiny.

In religious language, Melville states that Americans are the exceptional people of the modern age, as the Israelites were the chosen people of Biblical times. God has chosen America, and expects great things from this own country. Expansion of American territory, one of the primary concerns of those who believed in Manifest Destiny, was not motivated by greed for land and resources, but by a much nobler motive. It was, they argued, the duty of Americans to extend their borders and their influence as wide as possible, since by doing so, they would extend the influence of freedom, and of God.