Much of what makes The Passion of the Christ feel unlike any other Gospel film on screen does not come from the Gospels alone. Mel Gibson drew heavily on The Dolorous Passion of Our Lord Jesus Christ, a book of visions attributed to the German Augustinian nun Anne Catherine Emmerich, who died in 1824 and was beatified by the Catholic Church in 2004, the same year the film was released. Emmerich never wrote the book herself; it was compiled from her deathbed dictations by the poet Clemens Brentano, who sat with her for years transcribing what she described seeing.
Details that feel almost documentary in the finished film, the specific placement of the nails, a torturer taunting Jesus by name, Pilate's wife sending a cloth to Mary, trace back to Emmerich's account rather than to Matthew, Mark, Luke or John, none of which describe the crucifixion in anything like that physical detail. Gibson has said in interviews that he considers the visions a genuine aid to devotion rather than invented material, a claim scholars of the historical Jesus have not endorsed and generally treat as pious literature from a specific nineteenth-century mystical tradition rather than as a fifth source alongside the canonical Gospels.
The film credits nothing on screen beyond the Gospels themselves, which left most audiences unaware that a significant share of what they were watching, including several of its most quoted images, originated more than 1,800 years after the events depicted, in the private visions of a bedridden Westphalian nun.