It is amazing to think that some people actually believe they are good enough to get into heaven. Perhaps it is because we read so much bad news in the papers about others that we are quick to conclude that by comparison we are superior, and so deserving of a place in eternity.
It is even more amazing when you then consider that if a Christian were to stand in front of their friends and claim that they knew they were going to go to heaven, they would be regarded as being conceited, boastful and arrogant. How can they think that they are better than everyone else?
The fact that the same person can think themself superior to others, whilst at the same time criticising Christians for arrogance underlines one of the joys of living in a post-modern world. But how do we respond to the question, Why can’t I just be a good person? Isn’t it unfair of God to say that you can’t get into heaven unless you believe in Him, even though you have been a good person? Who does He think he is!
"People are basically good", wrote one poet, "it is only their behaviour that lets them down."
Believing or doing?
Jesus was once asked what we must do in order to please God and so gain entry to heaven: "What must we do to do the works God requires?" (John 6:28). They asked the question in the plural – what works – they wanted a list of good things to do. Jesus replied in the singular, "The work of God is this – believe in the one he has sent." But what makes belief so special? Surely what we do is far more important than what we believe? How can a good person, who is not a Christian, be denied access on the basis of belief?
The difficulty with the question of why it’s not enough to be a good person lies in the assumption that is made in it, namely that there is such a thing as a good person. Jesus was once asked the question, "Good teacher, what must I do to inherit eternal life?" (Luke 18:18). The assumption is clear: Jesus is a good person, good people go to heaven, so what must I do to also be in the same group? Jesus’ reply is surprising – "Why do you call me good?", he asks. Good question. Why is he good? Jesus goes on to answer his own question – "No-one is good but God alone." Now, if we accept the common assumption that only the good go to heaven, and God alone is good, who on earth is going? The answer must surely be no-one – except God himself.
The simple truth is that the issue is not about good people not getting into heaven. Alas, the problem is much worse! The question really is who on earth can get in at all? It is not a question of being more good than bad in order to qualify for eternal life. Jesus seems to define goodness in terms of being like God, and on that basis there are no good people anywhere.
The Good News
However, the Gospel is good news. The good news is that getting into heaven is first and foremost about forgiveness. Christians can be sure that they are going to heaven, not because they are good, but because they have received forgiveness.
Belief in Christ and faith in Christ mean much more than just thinking that He existed.
Jesus did not come into the world simply to set a good example, tell us to lead better lives or even to ask us to pray more and read our Bibles regularly. He came into this world primarily in order to make forgiveness for us possible. It is why, when he looked forward to the Cross, he stated that it was for this very reason he had come into this world. The real question as we have said is not about who is good enough to get in. The real question is how God makes it possible for anyone to get in at all. The answer is that we need to be forgiven, and that forgiveness is won for us through the Cross.
There is a second part to the question: Is belief important? Does it really matter? In our world, belief means little more than intellectual acknowledgment of something. However, the verb to believe in the New Testament signifies more than just that. Belief in Christ and faith in Christ mean much more than just thinking that He existed. They mean complete reliance and trust in him. In other words, it is about trusting in and relying on Jesus (His promises, His person, His life, His death and His resurrection). That is what makes salvation possible. Christians are not good people because they live morally superior lives to everyone else. They have been made good by having been forgiven what they have done wrong and by being given a goodness (righteousness, if you prefer) from Christ.
So good people will go to heaven. However, the path to goodness lies not in religious observances, but in the forgiveness of a good God, given to us through the Cross of Christ.
 I recommend The Cross of Christ by John Stott as reading on this subject. It is his most important book and one of the seminal works on this issue.