In studying John 3:1-21 this week, I was intrigued by this quotation from Thomas Constable, a professor at Dallas Theological Seminary.
Much of modern man's problem with the gospel is anthropological. It arises from a faulty view of himself. Fallen man generally views human beings as neutral if not good. Therefore the fact that God sent Jesus and Jesus came to save sinners seems only interesting at best. If man is good and not in need of salvation, we can applaud God's love as admirable. If man is neutral, we can take salvation or leave it. If we leave it, God appears unfair for condemning us. However man is not good or neutral but bad. He already stands condemned and destined to experience God's wrath. Therefore faith in Jesus becomes a necessary way of escape from that dreadful destiny.
http://www.soniclight.com/constable/notes/pdf/john.pdf (page 60)