The ion of the Christ is a 2004 American epic biblical drama film co-produced and directed by Mel Gibson from a screenplay he wrote with Benedict Fitzgerald. It stars Jim Caviezel as Jesus of Nazareth, Maia Morgenstern as Mary, mother of Jesus, and Monica Bellucci as Mary Magdalene. It depicts the ion of Jesus largely according to the gospels of Matthew, Mark, Luke, and John. It also draws on pious s such as the Friday of Sorrows, along with other devotional writings, such as the reputed visions attributed to Blessed Anne Catherine Emmerich.

The film primarily covers the final twelve hours before Jesus Christ's death, known as "the ion". It begins with the Agony in the Garden of Olives (i.e., Gethsemane), continues with the betrayal of Judas Iscariot, the brutal Scourging at the Pillar, the suffering of Mary as prophesied by Simeon, the crucifixion and death of Jesus, and ends with a brief depiction of his resurrection. The narrative is interspersed with moments in Jesus's life, such as The Last Supper and The Sermon on the Mount, and moments of Jesus' early life. The film was mostly shot in Italy. The dialogue is entirely in reconstructed Aramaic, Hebrew, and Latin. Although Gibson was initially against it, the film is subtitled.

The film was controversial and received polarized reviews from critics; some regarded the film a religious and holy experience, praising the performances of the cast, production values, and John Debney's musical score, while some found it to be antisemitic and the graphic violence to be extreme and emotionally draining. The film grossed $612.1 million worldwide, and became the fifth highest-grossing film of 2004 internationally at the end of its theatrical run. It is the highest-grossing (inflation unadjusted) Christian film of all time, as well as the highest-grossing independent film of all time. It was the highest-grossing R-rated film in the US, at $370.8 million, a record which remained unbroken for 20 years. It received three nominations at the 77th Academy Awards in 2005, for Best Makeup, Best Cinematography, and Best Original Score. A sequel, titled The Resurrection of the Christ, is in development.