The sinful nature in the believer is not removed in this lifetime. The sinful nature in the believer is not reformed in this lifetime. Don't kid yourself into thinking that you do not have a problem with sin. The sinful nature in the believer is not removed in this lifetime. The sinful nature in the believer is not reformed in this lifetime.
Sin dwells in and is manifested in the carnal believer.
Sin dwells in us, starting with the sin of Adam. The sinful nature in the believer is not removed in this lifetime. Not in this lifetime, but it will be removed when we are in our resurrected bodies. Because nothing good dwells in us. The flesh is a sinful nature, and is as evil today as when you were an unbeliever.