And although the Bible doesn't rule out sentient extraterrestial life, it leaves little place for it in the way it positions humankind above all the rest of creation.
Not over all creation.
And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
So God created man in his own image, in the image of God created he him; male and female created he them.
And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth.
Presumably aliens would get dominion over their own planets.
What I tried to say here is that even the cultural background simply to understand the life of Jesus would be far too complicated to tell them ...
I don't think that would be so much of a problem as you suppose. After all, the Roman Empire of the 1st century A.D. is so remote from our own experience that the Gospels might as well be set on another planet. I've never seen a slave or a shepherd or a fig-tree or a centurion or a crucifixion or a leper or ... well, you get the point. Nonetheless I can follow the story.
I can also follow science-fiction stories which are set on other planets amongst aliens which are deliberately made as alien as the author can possibly devise.
The other option would be that Jesus's sacrific would only pay for humankinds sin. And that each other sentient life would have had their own son of God who would pay for their sins.
You've missed an option, which is the possibility that no other species fell. Maybe God learned from the whole Eden incident not to leave forbidden fruit lying around.
Edited by Dr Adequate, : No reason given.
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