In an interview with L’Osservatore Romano, Fr. Jose Gabriel Funes, director of the Vatican Observatory, said that the possibility of life on other worlds is not contradictory to Christianity:
“How can we rule out that life may have developed elsewhere?” Funes said.
“Just as we consider earthly creatures as ‘a brother,’ and ‘sister,’ why should
we not talk about an ‘extraterrestrial brother’? It would still be part of
creation.”
Of course, the salient issue is whether such life would actually be sentient. We know that there is *life* on other worlds–that has already been proven.
The issue that bothers people is that, if there is *sentient* life on other worlds, that would seem to contradict the uniqueness of man according to Genesis.
C. S. Lewis wrote about this issue several times. Skeptics have proposed two euqal and opposite arguments from the known vastness of the universe:
1. There is sentient life on other worlds, and, therefore, man
is not unique in being made “in God’s image and likeness”. Therefore, to
these people, the incarnation would be ridiculous: why would God, they ask,
single out humanitiety from all other sentient races?
2. There is *not* life on other worlds, and man is unique in the
universe. To this prospect, the atheists say, “Why would God make the
whole universe just for us to inhabit one planet?”
Of course, St. Paul has the answer to both objectinos: the wisdom of God is absurdity to the Gentiles. C. S. Lewis responds to both claims, saying that, ultimately, it doesn’t matter.
But the more important laim is the one cconcerning the existence fo alien life.
Genesis says that God created tehw hole universe for us, so it’s not much of a leap to say the same thing, only that the universe is bigger than genesis suggests.
However, the existence of sentient life on other worlds *would* pose a problem. Lewis wrote his fantasy stories to speculate about how the salvation history of other worlds may operate differently from ours, and how the incarnatino on earth might extend to other worlds through our possible correspondence. In either case, Lewis argues that, if God *did* create other beings with souls, andm put them on other worlds, then he would have done so to have a differnt relationship with them.
The Lewis Crusade 