Jeffrey Hunter and Robert Ryan's car broke down on the way to the "Sermon on the Mount" scene. In costume as Jesus Christ and John the Baptist, they had to push the car to get it started.
The crucifixion scene had to be re-shot because a preview audience was offended at Jesus having a hairy chest.
This was the first big-budget major studio sound film in English to actually show Jesus' face. Most films at the time preferred to do shots of his hands or over-the-shoulder views.
The film began life as a very personal project for director John Farrow, who had recently made John Paul Jones, maître des mers (1959) for producer Samuel Bronston. Farrow, an ardent convert to Roman Catholicism and quite possibly the only Hollywood director ever to be made a Papal Knight, called the project "The Sword And The Cross" and planned to use only the words of the Bible for dialogue. His script was deemed impossible to film and producer Bronston elected to proceed without him. Farrow never directed a film again.