In the last question we saw that heaven is more about a relationship (with God, with Jesus, with other believers) than a long, white, sandy beach where people will enjoy a resort lifestyle for eternity. We also said that nobody naturally seeks God, or his will for their lives, so in this sense nobody is naturally good.
This is exactly what Jesus said to a highly moral young man who came to him in Luke 18. This young man could say that he had kept all the outward commandments since he was a boy. But sadly, he loved his money more than God. Jesus’ says that no-one is good except for God alone, the implication is that no-one can inherit eternal life, be saved, go to heaven (however you want to describe it). By the way, Jesus is not saying that people cannot do good things whatsoever (see Matthew 7:9-11) but he is saying that no-one is by themselves good enough to enter eternal life, even the most moral people like the guy in Luke 18. The disciples respond with a desperate question, “who then can be saved?” and Jesus’ responds by saying that only God can make it happen. The rest of the New Testament explains that it can only work on account of the sacrificial death of Jesus in the place of sinful people who turn to Jesus for forgiveness and reconciliation with God.
This means the quick answer to this question is “yes”: bad people who turn to Jesus in faith can enter heaven. On the flip side, those who continue to insist that they are good enough for God, and don’t want the death of Jesus in their place for forgiveness and reconciliation, will not enter eternal life. Only God can make it happen. Whether people consider themselves “good” or “bad” is not the crucial point; whether people turn to Jesus for salvation and life is the critical thing that determines where people spend eternity.