The performance of Harvey Stephens as the young Damien has invested the film with the chill of genuine credibility.
Time Out London
This apocalyptic movie mostly avoids physical gore to boost its relatively unoriginal storyline with suspense, some excellent acting (especially from Warner and Whitelaw), and a very deft, incident-packed script.
Suspenser starring Gregory Peck and Lee Remick as the unwitting parents of the Antichrist. Richard Donner's direction is taut. Players all are strong.
A bald-faced lamprey hitching its razor-tipped maw on the chassis of The Exorcist, The Omen’s Sunday-school parable of gothic Cathsploitation comes twice as thick and thrice as pious.
The Omen is a dumb and largely dull movie. No true connoisseur of kitsch will confuse the work of writer David Seltzer and director Richard Donner with the masterpiece of psychic manipulation contrived by William Peter Blatty and William Friedkin in The Exorcist, not to mention what the diabolical Roman Polanski made out of Ira Levin's Rosemary's Baby. [12 July 1976, p.69]