Here we are.... human beings -- homo sapiens.
We're smart, talented, inventive, productive, and capable of spiritual awareness. Is there a reason for that? Or no reason? Are we, as Bertrand Russell said, just "accidental collocations of atoms"?
We think that the "yes, there is a reason" argument makes more sense. There seems to be a purpose -- a will -- that drives the development of life. And intelligence. This positive force apparently out-powers the entropy that you would expect in a nothing-but-physical universe.
The New Christian take is that this positive, creative force stems from the nature of God. Think of God as love itself -- this intense, inexhaustible well of love -- shaped and instantiated by infinite wisdom. That sort of love would long for conjunction -- for making others happy, and for creating this reciprocal circuit of love and response. That sort of wisdom would enable the creation of a multi-faceted universe where such a reciprocation could thrive.
Right now, we're living in one of the facets of this universe -- the physical one. It's a sort of substrate, a grounding-out place, where free, rational human beings can develop and live, and have a chance to achieve spiritual development. There's a spiritual facet to the universe, too - another plane just as real as the physical one - where free rational human beings can keep on living after their physical bodies die.
If that's the case, what are we supposed to be doing? Essentially, our quest here on earth is to make an overall choice whether to go for spiritual freedom, with God's help, or whether to reject his leading, and go our own way, which ends up with us becoming enslaved by our own evil loves. That big overall choice gets built up from thousands of everyday choices.
For reference, among many places where Bible supports the idea of heaven and eternal life, here are some examples:
Jesus said, "In my Father's house are many mansions; if it were not so, I would have told you; for I go to prepare a place for you." (John 14:2)
In this way, therefore, you should pray: Our Father, who art in the heavens, hallowed be Thy name; (Matthew 6:9)
"And he said unto them, 'Verily I say unto you, There is no man that hath left house, or wife, or brethren, or parents, or children, for the kingdom of God's sake, who shall not receive manifold more in this time, and in the world to come eternal life.' " (Luke 18:29-30).