Commenting on P Money's review
WARNING! SPOILERS AHEAD!
Saying that Prochnow's character's motives are never quite clear shows me that P Money did not pay very close attention to this movie. Maybe I'm just obsessed, having watched this movie several times and being a huge fan of Jürgen Prochnow, but it very clearly states his "motives."
David Bannon, Prochnow's character, explains it to Abby (Demi Moore) quite clearly: (these probably aren't exact quotes, since I haven't seen the movie in years, but they're pretty close)
"I came as the Lamb; I return as the Lion."
Abby stabs David with a chef's knife
"Now, I am His Wrath."
***
"I can't die again, Abby. I wish I could." (David can't be the sacrifice this time. Someone else has to do it.)
***
"The Guf is empty." (if you've seen the movie, you'll remember what the Guf is; I've yet to research this and see if the story he tells is actually a part of Judeo-Christian mythology, although it seems to contradict the idea of God's grace being infinite. Then again, what isn't contradictory about Christianity?)
***
"I'm its witness."
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David Bannon (Prochnow) is a Jesus-like figure, although his statement that "I return as the Lion" suggests to me that, in this incarnation or assumption, he is more like the Messiah of Aaron (a warlike messiah) than the Messiah of David (the Christ).
God's grace has run out, and Abby and her unborn child are the keys to the survival of the human race and the replenishment of the Guf (I've also seen it spelled "Guph").
Abby has apparently had several miscarriages, at least one of which prompted a depression so severe that she attempted suicide by slitting her wrists (the wrong way, judging by the scars). When David reveals himself to her, and it is made clear that she is the only one who can possibly save humanity, he also grasps her by the wrists, exposing the scars, and says "How can someone who cared so little for life give life to the world?"
This is also, in a sense, Abby's opportunity for redemption for a previous incarnation in which she was (apparently) Mary Magdalen -- and seemingly had the opportunity to die in Jesus' (David's) stead. This again contradicts MODERN Christianity with its suggestion of reincarnation, but actually, reincarnation was once a tenet of Christianity (officially, it hasn't been since about the 4th century Council of Nicea, but at least two references to reincarnation still exist in the Bible).
I highly recommend this movie.