The phrase “the pit of being” is the first clue to the poem’s theme. Jarrell will return to the word “being” in his description of the knight, which concludes the poem. The poem is progressively about what it means to be human. The last words of the poem, “I am,” are formed from the verb “to be.” By placing such emphasis on these words, Jarrell suggests an existential reading of his poem would be appropriate. Similarly, Hamlet’s famous “To be or not to be” soliloquy has led critics to offer existentialist interpretations of William Shakespeare’s tragedy. Jarrell’s career paralleled a time when existentialism was a popular topic for discussion and poetic analysis.

A central point of existentialism is that existence, “being,” precedes the determination of one’s essence. This was true in the atheistic existentialism of Jean-Paul Sartre as well as in the Christian existentialism of Søren Kierkegaard. This view is the opposite of a more traditional Christian position known as Original Sin or, as the Bay Psalm Book of American Puritans expressed it, “In Adam’s fall/ We sinned all.” Original Sin is a subject central to John Milton’s Paradise Lost (1667, 1674). In Milton’s view, after the fall of Adam and Eve, essence, in this case sinfulness, forever precedes existence. One is born sinning and sinful; sin defines humanity. The existentialists, however, believed that one’s essence, or being, is the result of a life lived and choices made. An archetypal symbol for a life of choices is the journey, such as one finds in the picture of the knight upon his horse.

Jarrell asks of the knight, “The death of his own flesh, set up outside him;/ The flesh of his own soul, set up outside him—/ Death and the devil, what are these to him?” The painting invites the same question. Are the two figures opponents of the knight, against whom he may struggle as he makes choices along life’s journey? Are they mirrors of the knight, who is himself, by his vocation, an instrument of death and the devil? Though “outside of him,” Jarrell suggests they represent the choices that define his “being.” Of the knight, Jarrell says, “His being accuses him.” Good existentialist that he is, the knight abides by the choices he has made—“his face is firm/ In resolution, in absolute persistence.” His face and body language say “a man does what he must.” Humanity can do no more than define itself, assert its humanness in the face of Death and the devil.

In the engraving, Jarrell finds an emblem of what it means to be human and translates the picture into words that describe and interpret the human situation. The knight’s journey is the human journey. If the knight in the engraving is meant to represent someone specific, as some art critics suggest, there are few clues. In his poem, Jarrell takes a more universal view. Even the landscape is universalized. In the background, “His castle—some man’s castle—set on every crag” is either the knight’s goal or his point of departure. The knight “moves through this world,” and that is geography enough.

On the knight’s lance is “the bush/ Of that old fox.” Jarrell’s adjectives point to the fox as being more than just “any” fox. Traditionally, he symbolizes the devil; the fox brush, or tail, suggests the knight has encountered the devil before and bested him. Accompanying the knight is a dog that Jarrell makes “a sheep-dog bounding at his stirrup.” Looking at the dog, Jarrell sees “In its eyes the cast of faithfulness (our help,/ Our foolish help).” Faithfulness, like a dog at one’s feet, is “foolish help” because it is from outside, less than one’s pure inner being.

“So, companioned so,” by dog and horse, by Death and devil, each person journeys despite the certainty of death, despite the temptations of evil. A true knight “listens in assurance, has no glance/ To spare for them [Death and the devil], but looks past steadily.” It is not so much at what one looks as the very fact that “a man’s look completes [defines] itself.” No matter who the knight is, an adulterous Lancelot or a saintly Joan of Arc, he or she is not defined but defines.

Thus the poem concludes with the triumphant existentialist manifesto: “I am.”