Most christians these days do not believe this. They believe as long as they confess with their heart Jesus is the Christ they go to heaven, and little things along the way like murder and adultery do not have anything to do with salvation.
And they are wrong. Just because you believe in Jesus, does not mean you get a "get out of hell free" card, and get to do what you want.
You must truly have guilt over your sin, and want to stop your sin.(and try). Its one thing to try and fail again and again. But to not even try, or acknowledge you are doing wrong, will not "save" you.
Everyone has flaws and problems. Not everyone can come near to the example Jesus set for us to live by. But to just sit back and go "im fine the way I am" and not recognize your flaws and problems, you should not expect to go to heaven.
Heaven is "eternal happiness", and "eternal union with God". Someone who is not trying to better their lives when they do wrong, should not be allowed into paradise.
Its like saying a worker whom doesnt do their job well, and has many rude characteristics, and does not think they do anything wrong should be put on the employees of the month list.
So simply those who do not even try to better themselves despite all their flaws, nor feels any remorse for their sins, do not enter heaven.
A good example is Hitler. He was supposedly a Christian. But his actions reflected his true heart. His true beliefs(aka anti christian).
If you look at all the sinners Jesus hung out around, you will notice 3 things.
1. They follow and believe in Jesus. That He is the son of God, the Messiah.
2. They are sorry for their actions. Most after meeting Jesus, do acts of retribution to those they harmed(ex a unfair tax man gave back the money he stole, and MORE)
3. Jesus did not hang around nor accept those who sinned, but did not feel guilt, or remorse for their actions.
My sect of Christianity believes in a place called purgatory. It is where souls, of people who may have done anything from horrible things, to people who did not that horrible things, go to become pure to enter heaven.
Basically it is where your soul is purified to go to Heaven. From my understanding of purgatory, you only go there if you are already going to go to heaven. You dont go to purgatory to go to hell(from my understanding). Also you would spend more time there, the more unclean your soul is(so clean souls, may nearly skip this step)
But again. There are many false Christians. They go and think that they are saved if they just show up to church every week. The may even preach things that are opposite to what Christianity is about.
I myself, do not consider myself saved. I believe that Jesus died for my sins. I believe in God the FATHER(God behaves and is our father, while we are his unknowing, ununderstanding children(if you read the bible from this perspective "no johnny you need to eat your vegetables. You cannot eat ice cream for dinner" then suddenly many of the "sins" that are mentioned make perfect sense)
I believe in all that stuff though. I just havent taken the step to submit myself to him, and let him guide my life. Its hard to do. You must be willing to give up all that you have to do his will. You must trust that he will provide for your needs. (like a kid trusts his parent, and listens to him)
Again though. Have a great night guys!