What is sin?

Sin is now a foreigner in our land. An outsider trying to get back in. It no longer holds power over us and we are under no obligation to let it back in. (Rom 6:6-7, 8:12) If I do what I do not want to do its no longer I (my true self as redeemed by Christ) who do it, but the sin living in me that does it (Rom. 7:20) — but, by sending Jesus as a sin offering, God condemned sin in sinful man so that the righteous requirements of the law might be fully met in us!.. (Rom 8:3-4a)

Does this mean there is no more sin living in us? I think so.  Sin is a foreign object, not part of who the believer is.