That is what Jesus offers to us, by going to the cross for our sins paying for them by the shedding of His most precious blood.
I've heard folks say, “well, I'm a good person”. It doesn't matter whether you're a good person. The fact is, God is so holy, so incredibly holy that without clothing oneself in the righteousness of Jesus, we have no hope of standing before a holy God. You cannot add to or take away from the work of the cross.
When Jesus said, “it is finished”, he meant that the payment for sin and the perversion that occurred with the fall man has been corrected. By one man sin came into the world, by Jesus the curse of sin and death has been conquered.