Final answer:
John Winthrop believed a failure to live up to Puritan ideals in America would lead to God's judgement, public shame, and the collapse of their community, which was meant to be a 'City upon a Hill'.
Step-by-step explanation:
John Winthrop, the leader of the Puritan community in the Massachusetts Bay Colony, delivered a sermon titled "A Model of Christian Charity" wherein he articulated his vision for the colony. Winthrop believed that by adhering to their strict Puritan ideals and living as a model Christian community, they could establish a "City upon a Hill", serving as a beacon of righteousness to the world. Should they fail to live up to their ideals, Winthrop warned, the Puritans would face the judgement and wrath of God, failing not only themselves but also the mission to spread the Christian gospel. He stressed that such failure would result in public shame and ensure that their undertaking in New England would crumble and serve as a cautionary example to others.