Hell - the very word stirs up so many emotions and questions. It is a subject that should not be taken lightly by those who believe in a literal hell and those who disbelieve in its existence. The ramifications of a literal place called "hell" are huge, therefore it should not be viewed as a simple, easy thing.
Christians should view hell with discomfort, both in the fact that people are there and will be going there and that we were once destined for that place. God, I believe, is also uncomfortable with hell and does not like its existence. But there is a difference between being uncomfortable with something and having a rational considered judgment that it is wrong. I believe the only moral choice God could make is to allow people, who show no interest in making it to heaven on His terms, the choice of hell.
Ezekiel 33:11 tells us that God takes no pleasure in the death of the wicked. Hell is not something that God enjoys, but rather something that must exists because of the free will of human beings. Many decide to live their lives completely separate of God. They have no desire to have a relationship with Him and never attempt to come to Him on His terms. Those people would not be happy in heaven, since heaven is not some super amusement park filled with all of our favorite earthly things, but rather a place where God is the focus of everyone's attention and worship. If on this earth, the last thing I desire is God, then why would I suddenly be happy with seeing Him and worshiping Him? God is essentially giving people what they want. If you don't want God, His rules or His ways, then eventually you get what you want. It follows the old adage that God is gentleman and does not force Himself on anyone.
Dr. J.P. Mooreland gives the illustration of being around someone who is unbelievably good looking, extremely attractive, a great deal smarter than you, basically much more interesting than you. In a social situation, people flock to him and want to listen to him, not you. Suppose you don't like that person, but you're in a room with them 24-hours a day for 30 years. How miserable would that be? You must magnify that an infinite amount of times when looking at being around God for eternity. If you do not want God, then heaven would essentially be "hell" for you.
Forcing people to do things against their will basically dehumanizes them. Look back at the history of our world. Many of the greatest evils were committed when people were viewed as less than human - slavery, holocaust, abortion, etc. God refuses to dehumanize us. He created us in His image. We have intrinsic value, we are not simply a means to an end. Forcing everyone to go to heaven strips people of their dignity to make their own decision, it denies them their freedom of choice, it basically treats them as a means to an end. When God allows people to say "no" to Him, he actually respects and dignifies them.
Many images have been used to describe hell, but in essence hell is simply separation from the best thing in the universe - God. There will be no red-clothed, hoof-footed man poking people with pitchforks. The most painful thing in hell is simply the separation from God, and all that is good, since goodness comes from God. The isolation from Him brings about all suffering.
One common complaint about hell is the fairness aspect of it. How can someone who is a really good person be punished the same as Hitler or other mass murderers? Mooreland believes that the Bible teaches there will be different degrees of suffering and punishment. He uses Jesus' words in Matthew 11:20-24 to support this claim. (Speaking of Jesus, many revere His comments to "love your neighbor," but reject his teaching on hell. Jesus taught more about hell than anyone else in the Bible. In fact He mentions hell more than he does heaven.)
The fairness question also flows into thoughts on other religions and "those who have not heard." For those who have heard, it falls around the question of who is in charge. If God, being the Creator and Sustainer of everything, decides that there is to be one way in to heaven, then who are we to challenge Him and say that He must accept our way. God, in His graciousness and love, has provided a way for us to enter into His presence for eternity. We should gladly take that established way.
If you are trapped in an area surrounded by a forest fire and I call you to tell you that there is only one road by which you can escape safely and all the other roads will eventually be overtaken by the fire. What good would it do to argue with me about being fair to other people on other roads? Am I being intolerant or helpful? If God has established one way to get to Him and I have found it, it would be virtually evil for me to tell others to try another road, all the while I know those other roads led in the opposite direction.
As for people who have never heard of Jesus and the Gospel, I have to trust that God will deal justly with everyone. I believe God will judge based on knowledge. As I have said before, I think God honors His word when He says, "if you seek Me, you will find Me." For those who live in isolated areas away from any Christian influence, God says He will be found by them if they seek Him. Missionaries have founded whole communities of unreached people worshiping Jesus. They tell the missionaries that He appeared to them. Many Muslims have visions of Jesus speaking to them, which leads to their salvation. God is just, He will do the right thing.
These statements will never totally answer every question about hell. There are questions that I have myself, but for me is falls under a realm of trust. Having known God personally, having seen His Word as true, knowing His personality, I have to give Him the benefit of any doubt I may have. He has proven Himself to be just, loving and holy. Those attributes will be satisfied when it comes to hell and who is there. We are on thin ice, when we claim moral superiority to Jesus (who seemed to have no problem with the doctrine of hell). He knows what is best and He will do that. The simplest thing that I know to do is to look at the character of Jesus and see if He is trustworthy. I believe He has proven Himself worthy of our trust on the easy things as well as the difficult issues such as hell.
Much of the information for this post was from The Case for Faith by Lee Strobel.