Or this place:
I don't know anyone who is a perfect saint, and I don't know any serial killers (not personally anyway). Would a loving God only give us two options? Is it either all or nothing? Couldn't there be a place in between?
We believe that God loves ALL of his children, no matter what they do, and has prepared a place for them. That is why the Mormon doctrine of three heavens does not seem strange to me at all. We don't really call them heavens, though. We call them kingdoms.
The best kingdom, the kingdom in which there is the greatest potential for happiness, is called the Celestial Kingdom. It is called that because the glory of this kingdom is like that of that of the sun.
In this kingdom, all the people who believe in Jesus Christ and were baptized will come to dwell. These individuals kept the commandments of God on the earth and now they will spend eternity in glory and excellence. They will continue to improve and learn and expand. This is the only kingdom in which men and women can continue together as married couples and families. People in this kingdom are busy creating, building and serving. It is beautiful beyond description and it is in this kingdom that Jesus Christ lives and reigns.
The next kingdom is the Terrestrial Kingdom. It compares to the Celestial Kingdom the way the moon compares with the sun. The people who come to this place are honorable and good men and women who received a testimony of Christ, but were never baptized by one with authority. Also people who were baptized by one with authority but were not valiant in their testimony of Jesus will come to this kingdom. This world is also beautiful and wonderful.
The third kingdom is the Telestial Kingdom, which compares to the other two kingdoms like the light of the stars would compare to the sun and the moon. This kingdom will be peopled by what we would consider "bad" people: murders, etc. It is the place for people who never received a testimony of Christ. But even this kingdom "surpasses all understanding" and is a place of glory.
There is one more place, and it is not a kingdom, and it has no glory. It is not heaven.
This place is called Outer Darkness. To get here you would have to willingly refuse the Savior and become a Son of Perdition. You would need to know, beyond any doubt that Jesus died for your sins, that He is The Christ and still reject His atonement. Joseph Smith said it would be like walking outside, looking up at the sun and then say that the sun is not shining. There is no forgiveness for these souls and they will live with Lucifer and his angels.
Luckily, few people will go here.
As Latter-Day Saints it is our greatest hope to attain the glory the Celestial Kingdom. Not only because we can be with our families forever, but because we can continue to create families. Families and family creation is central to our doctrine. That is why we believe so strongly in marriage between a man and a woman because it is only between a man and a woman that life can be created.
We believe that God is a just and loving God, and that he has provided a place for all of us to go; a place where we would feel the most comfortable living out eternity. We will be sorted into these kingdoms by our thoughts and our actions, so it will be a place of our own choosing. In His wisdom God prepared a place where each of us can be as happy as we choose to be.