Factual error: The priest says that St. John saw the number 666 in his vision, but it was actually 999 inverted. I'm not sure, but I don't believe St. John read modern Arabic numerals like we do. Didn't he read Roman numerals? I think if St. John saw the number 666, it would actually be DCLXVI.

Continuity: After the priest writes down 666 on a piece of paper, he holds it upside down to reveal that it is 999. When we cut back to him a few seconds later, the numbers look completely different.

Continuity: After Arnold drops through the newspaper stand from the helicopter and chases after the priest, we never really get to see him disconnect his harness. As a matter of fact he takes off running with it still attached.

Continuity: In the scene were Arnold disconnects the carriages of the train, near the end, he has to jump across the gap. When we first see the gap it is a certain distance, the camera angle changes and it's a bigger gap, then the angle changes and it's closer, there is no way Arnold could have jumped that big gap.

Continuity: In the scene where Satan enters the church demanding to know where Christine York is, one of the priests approaches him with a crucifix. The camera is facing the priest, Satan grabs the crucifix and stabs the priest right in the centre of his forehead (just above the eyebrow line). The camera angle changes to facing Satan and when the priest hits the deck, the crucifix is sticking out of his head higher up and above his left eyebrow.

Continuity: In the scene when Satan gets out of the car and turns up his collar with no gloves on his hands, the same scene (picture from the other side) he turns up his collar and his hands are already gloved.

Continuity: Just when Jericho catches the priest jumping off the rooftop with Jericho hanging from the helicopter. in the next shot, his partner yells, "He's Got Him!" When the shot goes back to Jericho, he's hanging from the line with no priest in his hands. The next shot shows him hanging from the helicopter, holding on to the priest.

Continuity: At the beginning of the movie, when Arnold and the stryker security crew are protecting Satan in the limos pay attention to the crowd. Right when they arrive at the building, and begin to get out the vehicles the pedestrians begin to duck and run for no apparent reason. Especially noticeable in the shot, right before Arnold says "We're exposed"

Continuity: When Satan shows Arnold the bandits who killed his family, Arnold tries to catch one of them, falls through the bandit, toppling the Christmas tree. But when Satan changes the flat back to normal (with no tree) we can see the tree standing upright as it disappears.

Continuity: In the church at the end when the windows are shattering, Arnie's got his right arm protecting his face in a wide shot and a closeup, then in the next shot (behind him) his left arm's up. we then cut in front of him again and his right arm's back up.

Factual error: As the subway trains are disconnecting, Arnold fires a 203 grenade launcher at Satan, knocking him back onto the other train. A 40mm grenade doesn't arm itself until about 15-25 meters, so unless Satan jumped extremely far, the round would not have detonated.

Continuity: After the baby is born, the nurse puts a blue towel on her, completely covering her chest. The next shot, the baby's chest isn't covered.

Continuity: In the train sequence near the end as Arnold shoots Satan out of the train, he flies toward the other carriage and starts to fall short, then in the next shot he lands ass first in the train.

Continuity: In the subway scene, after Christine has given the bum the money and he shatters, his face hits the floor with the top of his head towards Christine, and his face away from her, when the shot changes to a close-up, his head has turned, and is facing her.

Continuity: When Arnie is in the church the things on the tables keep changing - in one shot we candles on it but in the next we see a cross.