This is something the human mind struggles with. I am just an old sinner, I am as dirty rags, I am as a old worm wiggling in the dust. With that mentality we are saying. What Jesus did on the cross was inadequate to do the job He was sent to do . If we don't know who we are , we won't know our rights.
Righteousness is a gift.
There is nothing you can do to acquire it. It is yours free and clear the moment you accepted Jesus as your deliverer. The moment you ask Him to come into your life, you were the righteousness of God. He said I in thee and they in Me. We have to walk in the fullness of what Jesus paid for.