The old nature is impure, ignorant, and insensitive (Eph. 4:17-24). Paul doesn’t encourage us to hide it. He challenges us to cast off the old nature and put on something new.
“Lost” is a biblical word describing the sad spiritual condition of people who need Jesus. In his letter to the Ephesians, Paul examines what “lost” means (Eph. 2:11-13).