Quote:
John 16:8-9 (New International Version)
8When he comes, he will convict the world of guilt in regard to sin and righteousness and judgment: 9in regard to sin, because men do not believe in me;

This verse is pretty simple, it is a sin not to believe in Jesus.

Quote:
John 8:34-35 (New International Version)

34Jesus replied, "I tell you the truth, everyone who sins is a slave to sin. 35Now a slave has no permanent place in the family, but a son belongs to it forever.


If we sin we are a slave to sin, and can not remain with God forever.

Quote:
John 8:36 (New International Version)
36So if the Son sets you free, you will be free indeed.


The Son has the power to set us free.

How did he set us free?

Quote:
John 3:16-18 (New International Version)
16"For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. 17For God did not send his Son into the world to condemn the world, but to save the world through him. 18Whoever believes in him is not condemned, but whoever does not believe stands condemned already because he has not believed in the name of God's one and only Son.


If the son has set us free how can we be made sons and remain with God forever?

Quote:
John 1:12 (New International Version)
12Yet to all who received him, to those who believed in his name, he gave the right to become children of God—


there is no way to get to heaven expect through Jesus.

Quote:
John 14:6 (New International Version)

6Jesus answered, "I am the way and the truth and the life. No one comes to the Father except through me.


now that you've heard excuse to keep sinning.

Quote:
John 15:22 (New International Version)
22If I had not come and spoken to them, they would not be guilty of sin. Now, however, they have no excuse for their sin.