The phrase "a city upon a hill" refers to those who are forging a new path and are examples to others in the way they live and function. The words are often used to describe people of faith but are also used in politics.
Jesus spoke to his followers in Matthew 5:14, "Ye are the light of the world. A city that is set on an hill cannot be hid." According to U.S. History.org, John Winthrop said of his fellow travelers to Massachusetts Bay Colony in 1630, "We shall be as a city upon a hill, the eyes of all people are upon us." He knew they were going to a new place to establish a new way of life, and the world was watching. He and the others on the trip wanted to show other people how to accomplish such a mission. President-elect John Kennedy quoted Winthrop in a speech to the people of Massachusetts regarding how he wanted his administration and his nation to lead.