I really enjoyed this. It was great to see Garland pushing so confidently into wild abstraction. I don't know what it means, aside from the feminist, religious, and mythological themes being obvious. But I can clear up a literary reference I found striking. The vicar quotes some lines from William Butler Yeats' poem
Leda and the Swan:
Yeats wrote:A shudder in the loins engenders there
The broken wall, the burning roof and tower
And Agamemnon dead.
Yeats' poem is a retelling of the story of the rape of Leda, where Zeus in the shape of a swan overpowered Leda, after which she bore twins, Helen and Klytemnestra. Helen of course was widely blamed for the Trojan war (not unlike the treatment of Eve), and, depending on the source, Klytemnestra either murdered her husband, Agamemnon, or encouraged her lover to do it. Two women whose lust and violence brought down two noble houses, those of Priam and Agamemnon, and for centuries have been symbols of female baseness. (Never mind of course Menelaos' jealous wrath at is wife going off with a younger, prettier man, or Agamenon ritually sacrificing he and his wife's eldest daughter, Iphigenia, to his wife's horror and despair.)
Not as much remarked on is that those two women fated to end empires with their violence and wantonness were the product of male violence, a male violence inextricable from divine power and authority. When Harper asks the Vicar, "What the fuck are you?", he whispers, "a swan." It's not hard to see parallels: Harper, a victim of male violence who is unfairly blamed for the aftermath; the Men, including the husband, needing her love above all things and whose subsequent violence engenders endless self-begetting cycles of further violence and need. Each of these cycles is born entirely of itself, and yet each one blames someone outside of itself. Endlessly self-begetting, endlessly externalizing. The abstraction with which it's presented turns this into more than just an interpersonal critique. It's a vision of culture as well, the way culture feeds on its own products, self-perpetuating cycles of myths and stories that blame the Other for their own self-generating content.
There are lots of images of fertility, but one of the most unsettling before the final phantasmagoria is a seed floating into the carcass of a deer. The next shot of that carcass shows it to be in advanced decay. The significance is ironic: rather than rebirth, rot has been quickened. Or maybe not: there are plenty of maggots, so the fertility symbol is not of rebirth but of the way some lifeforms feed on the death and destruction of others to sustain themselves.
It does seem that pagan fertility myths are being used as metaphors for cultural attitudes to gender.