John Donne is an early seventeenth-century literary trailblazer. He is the most important of a group of poets later called the metaphysicals. He was also, in his role as an Anglican priest, the author of important meditations and sermons.
Donne's metaphysical poetry broke with Renaissance conventions that called for measured, regular verses using rhyming couplets and a conventionalized set of metaphors and imagery. Donne left all that behind as he strove to create the most unusual and original metaphors he could fashion, called metaphysical conceits, to express his thoughts on religion and love. For example, in his poem "A Valediction: Forbidding Love," he compares himself and his beloved to the the two legs of a compass, a tool used to draw circles, showing that even when the legs where far apart, they were still joined. Nobody had ever used a metaphor like that to describe the relationship of lovers who are physically separated.
Samuel Johnson, who coined the term metaphysical poets, disliked Donne's fractured, difficult, and intellectual writing, but starting with the Romantic poets of the early-nineteenth century and gathering steam under the approval of T. S. Eliot in the twentieth century, Donne's stature as an important and groundbreaking poet has grown.
Donne is also known for his prose writing, the most famous of which is Mediation XVII in which he advises listeners that all people are interconnected. The piece is famous for using geographic metaphors to describe human interdependence, such as:
No man is an island entire of itself; every man is a piece of the continent, a part of the main
It is Donne's fresh and startling originality as a writer and his ability to hit on striking and unusual images and metaphors that has been the chief source of his fame.