We need to understand; none of our good deeds can make us perfect or wash our sins. Knowingly or unknowingly we commit sins. In fact we all came with sin into this sinful world. King David confessed before the Lord “Behold, I was brought forth in iniquity and in sin did my mother conceive me” (Psalm 51:5).
On the outside we might put on a good show, but if we look closely at what’s going on inside our hearts it’s a lot messier than we’d like to admit. So what did Jesus do and said? Well, first, Jesus lived in a way that demonstrated compassion with the most marginalized. He showed equal respect for men and women. And He said things like, “theft, greed, envy, slander; sexual immorality, all those evils things come from inside and defile a person” (Mark 7:22-23). However well we try to hide it; somewhere on the inside we all have a problem with sin.
Sin stands in the way of God's great plan and purpose for human life — directly in opposition to our eternal salvation as potential sons and daughters in the everlasting Kingdom of God. One of the problems is, we have a God complex. We try to run the show, and we choose things other than God to give our lives meaning and identity and purpose. And it never works. Because only God is big enough to build our lives upon. Only God can give us our true identity and a love that never leaves us. Here’s the good news. Jesus came to earth because of our sin; because of our refusal to let God be God. But God never stopped loving us. He sent his son Jesus to rescue us. So to return to the above topic question, “Why would decent person need forgiveness?” Because no one is as good as we might think. The scripture says “there is not a righteous man on earth who does good and never sins” (Ecclesiastes 7:20). We have all tried to be God rather than worship God. We all need forgiveness. And Jesus came to offer us forgiveness for our sins, and to offer us through his Spirit a new identity, a new heart, a new hope to live a new life.
God’s forgiveness does not remove our human nature – the negative tendency within all people to commit sin. Because we still live in this present evil world, and still have human nature, we will sin again. Our human nature is a product of sins that we committed in the past and the effect on our lives of the sins committed by others as a result of the influence of Satan over the entire world. Apostle Paul candidly spoke of his ongoing struggle against human nature (Romans 7:14-25). However when we repent and confess our sins God is faithful to forgive all our sins. And until we are not forgiven by Christ we will not inherit the kingdom of God.