Even as a child I had the understanding that if Heaven is a perfect place then I would not fit there because I was not perfect. Perhaps other really good people would be suitable to reside there, but I certainly would not. Later in my life someone told me that if I went to heaven being the same person I am now, even as a Christian, that I would mess-up the entire domain. Logically that made sense to me.
Thankfully, not a single believer in Jesus will enter heaven the exact same person that they are now. Even though on earth we are declared righteous by God because of the imputed righteousness of Christ, we are currently imperfect. Our earthly imperfection will be remedied instantaneously by God at the moment of our transition to His presence. We will, by God’s power, become in reality what we are now positionally in His sight. The process and struggle of our ongoing sanctification will end in glorification as we are made completely holy.
This does not mean that we will lose our identity or personality, only the presence of sin around us and the infection of sin within us. Therefore, you and I who are not currently fit for Heaven will become so. It is fascinating to ponder what you will be like without the presence of sin within or upon you.
The Acts of the Apostles, Part 64 – Outline (PDF)