The Evolution Connection
The idea of extraterrestrial life stems largely from a belief in evolution. Recall that in the evolutionary view, the earth is “just another planet”—one where the conditions just happened to be right for life to form and evolve. If there are countless billions of other planets in our galaxy, then surely at least a handful of these worlds have also had the right conditions. Extraterrestrial life is almost inevitable in an evolutionary worldview.
However, the notion of alien life does not square well with Scripture. The earth is unique. God designed the earth for life (Isaiah:45:18For thus saith the LORD that created the heavens; God himself that formed the earth and made it; he hath established it, he created it not in vain, he formed it to be inhabited: I am the LORD; and there is none else.
See All...). The other planets have an entirely different purpose than does the earth, and thus, they are designed differently. In Genesis 1 we read that God created plants on the earth on Day 3, birds to fly in the atmosphere and marine life to swim in the ocean on Day 5, and animals to inhabit the land on Day 6. Human beings were also made on Day 6 and were given dominion over the animals. But where does the Bible discuss the creation of life on the “lights in the expanse of the heavens”? There is no such description because the lights in the expanse were not designed to accommodate life. God gave care of the earth to man, but the heavens are the Lord’s (Psalm:115:16The heaven, even the heavens, are the LORD's: but the earth hath he given to the children of men.
See All...). From a biblical perspective, extraterrestrial life does not seem reasonable.
When we consider how the salvation plan might apply to any hypothetical extraterrestrial (but otherwise human-like) beings, we are presented with a problem. If there were Vulcans or Klingons out there, how would they be saved? They are not blood relatives of Jesus, and so Christ’s shed blood cannot pay for their sin. One might at first suppose that Christ also visited their world, lived there, and died there as well, but this is antibiblical. Christ died once for all (1 Peter:3:18For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit:
See All...; Hebrews:9:27And as it is appointed unto men once to die, but after this the judgment:
See All...–28, Hebrews:10:10By the which will we are sanctified through the offering of the body of Jesus Christ once for all.
See All...). Jesus is now and forever both God and man; but He is not an alien.
One might suppose that alien beings have never sinned, in which case they would not need to be redeemed. But then another problem emerges: they suffer the effects of sin, despite having never sinned. Adam’s sin has affected all of creation— not just mankind. Romans:8:20For the creature was made subject to vanity, not willingly, but by reason of him who hath subjected the same in hope,
See All...–22 makes it clear that the entirety of creation suffers under the bondage of corruption. These kinds of issues highlight the problem of attempting to incorporate an antibiblical notion into the Christian worldview.
Extraterrestrial life is an evolutionary concept; it does not comport with the biblical teachings of the uniqueness of the earth and the distinct spiritual position of human beings. Of all the worlds in the universe, it was the earth that God Himself visited, taking on the additional nature of a human being, dying on a cross, and rising from the dead in order to redeem all who would trust in Him.
http://www.answersingenesis.org/articles/nab/are-ets-and-ufos-real