But I am good person. Aren't I?

 Read Romans 3.

The question that determines where a person will spend eternity is, "What have you done about your sin?"  That question penetrates to the core of who we are and why God would ever accept us.  Many are the attempts of humans to justify themselves but not one of man's ideas will ever be satisfactory before a righteous and holy God.

Our parentage does not count. (v.9a)
Being in a particular group does not count. (v.9b)
Keeping the commandments does not count. (v.20)

But if I keep the Ten Commandments and do certain things won't I be good enough for God to accept me?  The answer here is clearly no.  Why?  Because none of those things address the root issue.  The problem is our personal sin.  We are judged by God's word not ours.

How pervasive is sin?
v.9 "...all...are under sin"
v.10 "None is righteous, no, not one."
v.11 "no one understands; no one seeks God."
v.12 "All have turned aside...no one does good, not even one."
Sin affects a person's speech (vv.13-14)
Sin affects a person's behavior (vv.15-17)
Sin affects a person's thinking (v.18)

Some respond by trying harder.  "We have all become like one who is unclean, and all our righteous deeds are like a polluted garment...worthless..."  (Isaiah 64:6)

Some reject what God has said and choose to believe in something else.  But that does not change the facts.  "...so that every mouth may be stopped, and the whole world may be held accountable to God." (v.19)

Some react to Christians and churches who have disappointed or hurt them.  "Does their faithlessness nullify the faithfulness of God?  By no means!  Let God be true though every one were a liar..." (vv.3-4)  There are simply no acceptable excuses for not dealing with one's sin.

What is the answer?
In the entire universe, there is only one solution to sin.  "...the righteousness of God through faith in Jesus Christ for all who believe...and are justified by his grace, through the redemption that is in Christ Jesus..." (vv.22-24)  I confess my sin to God and He forgives me, not because of my goodness but because I believe Jesus paid for my sin on the cross.