To me the ending reads as an inversion of the Gethsemane story*:
· Jesus stays awake all night praying/Espinosa indulges a carnal sin and sleeps
· Jesus spends the night alone (sleeping disciples don’t count)/Espinosa has a woman in his bed
· Jesus knows what’s going to happen and still chooses to go/Espinosa doesn’t know what’s happening and has to be forcibly taken
Also of note, when Espinosa swears not to tell, he’s reenacting the “messianic secret”, where Jesus repeatedly tells his disciples not to tell others about the wonders they’ve seen. This is true in all 3 Synoptic Gospels, although, oddly, the Gospel of John has Jesus putting everything on blast.
Re Social Darwinism: There’s no reason to establish that the Gutre were originally Scottish (aka very, very white) unless it was to establish them as a eugenicist’s cautionary tale. I don’t know Borges beliefs on race - I’ve read conflicting things. However, the publication date on this puts it during the time when he was a supporter of the fascistic National Reorganization Process in Argentina. I’m not sure if that’s significant or not.
I thought the ending was very telegraphed, from his comment about a god being willing to be sacrificed being one of the only interesting stories to Mr. Gutre telling him not to worry about the repairs. However, maybe that’s just me.
* N.B. As a former Fundamentalist, I know the Protestant Bible pretty well. I have a nodding acquaintance with Catholic theology, but I do not know it well at all. So, all of my comments are from a Protestant background.