"In Santa Maria del Popolo" delves into the themes of blindness and revelation, exploring how religion and art serve as conduits for illuminating the human experience. The poem’s author, Thom Gunn, candidly reveals in "My Life Up to Now" (1977) his gratitude for being raised without religious influence. He credits this upbringing for his attraction to existentialism, a philosophy advocating for personal meaning-making in an indifferent universe. For Gunn, poetry becomes the chosen medium to craft and express that meaning. Within this context, he examines the interplay and relative potency of religion, art, and poetry in shedding light on our existence.

Gunn found a kindred spirit in Caravaggio, a painter renowned for his audacious, sensual, and individualistic nature. Caravaggio’s reputation for infusing traditional motifs with homoerotic elements resonated deeply with Gunn, who often drew parallels between his own work and that of the Baroque master. Addressing Caravaggio as a fellow artist—“O wily painter”—Gunn admired his bold approach, praising the painter’s ability to distill chaos into a singular moment of intensity: “limiting the scene/ From a cacophony of dusty forms/ To the one convulsion.” Here, the use of “cacophony” signals the poet’s alignment with sound over sight, further cementing their artistic bond.

Gunn’s contemplation of Caravaggio’s work leads him to ponder deeper meanings, particularly in the painting's depiction of Saul’s conversion. Gunn zeroes in on the tension between “Candor and secrecy inside the skin,” suggesting that the painting holds a hidden narrative. This is where Gunn speculates about the possible homoerotic undertones, drawing connections to characters in Caravaggio’s portfolio, like the “firm insolent/ Young whore in Venus’s clothes” and the “pudgy cheats” and “sharpers” found in works such as Concert, Lute Player, and Bacchus.

The narrative surrounding Caravaggio’s untimely death remains enigmatic, with Gunn embracing the account that he met his end violently at the hands of male prostitutes he had encountered on the streets. This speculation feeds into Gunn’s exploration of a shared secret—a clandestine sensuality—that might have been shared by Saul, known for his misogynistic tendencies, and paralleled by the homoerotic inclinations of both Caravaggio and Gunn himself.

In a dimly lit corner of Santa Maria del Popolo, a solitary man stands, embodying the essence of existential philosophy. This man, Paul, is not defined solely by his unique erotic inclinations but by the "alternate/ Candor and secrecy" that segregate him from the rest. His existence mirrors the existential confrontation with "nothingness," a struggle navigated through embracing rather than shunning it. While the women in the church quietly harbor their secrets within the confines of their minds, analogous to the sacred confessional, the artist dares to reveal the "Candor and secrecy inside his skin." This raw honesty sets him apart, marking him as an outsider yet a seeker of truth.

In this sacred space, the saint, too, acknowledges his own state of fallibility, a candid admission of human imperfection. The narrator of this poignant scene, upon exiting the church, confesses to leaving "hardly enlightened." This lack of enlightenment might suggest that the somber revelations imparted by Caravaggio's painting weigh heavily upon him. Despite this, the profound impact of the artwork sparks the creation of his poem, a journey of enlightenment that is far from effortless.