Creator Jon Erwin's fascination with the story of King David began in his youth, and he started writing the script as a teenager after visiting King David's tomb in Jerusalem, an inspiration that eventually led to the series decades later.

Amazon's interest in producing a high-budget biblical series was sparked when the film On a Wing and a Prayer proved unexpectedly popular on the platform.

Amazon initially ordered only one season, even though Erwin had written a script intended to span three seasons.

The casting search for the lead role of David took four months before newcomer Michael Iskander was selected, marking his first major acting credit.

Michael Iskander partly secured the role of David because he had competed in shot put and discus in high school.

Goliath actor Martyn Ford is 6'8" and 320 pounds in real life, but is portrayed as 9'9" tall in the series through forced perspective and digital enhancements.

Principal photography took place primarily in Greece, notably in the region of Fyli, with additional filming in Calgary, Alberta, Canada, after location scouts had also considered Morocco, Jordan, Italy, and Israel.

Over 700 people were involved in the production, which was filmed entirely on the Sony FX3 camera using a 2:1 extraction, Atomos external recorders for ProRes RAW capture, and DJI RS4 gimbals.

The show's cinematography was heavily inspired by the visual style of the film The Creator.

Generative AI tools such as Runway, Luma, Kling, Topaz, Magnific, Midjourney, and Google Nano Banana/Flash were combined with traditional VFX software like Unreal Engine, Nuke, Photoshop, and After Effects to create Goliath's origin sequence in season 1, episode 6, and other effects like battle scenes and horse close-ups; season 1 included 72 AI-assisted shots out of 850 total VFX shots, with season 2 seeing roughly a fivefold increase to as many as 350–400 AI shots.

The score was composed by Kevin Kiner along with his children Sean and Deana, a trio who had previously worked together on Star Wars: The Clone Wars and Narcos: Mexico, blending traditional Middle Eastern instrumentation with contemporary orchestral elements.

The series attracted 22 million viewers within its first 17 days, prompting Amazon Prime Video to renew it for a second season, and had reached more than 44 million viewers worldwide by the time season 2 was released.

On Rotten Tomatoes, 71% of 7 critics gave the series a positive review, with an average rating of 7/10, and reviews ranged from praise for its production values and respectful depiction of Jewish traditions to criticism from Variety calling it 'wooden and cheap-looking' and positioning it as a prequel to The Chosen.