Why is God's righteousness imputed to believers?
God's righteousness is imputed to believers because they have believed what Christ has done on their behalf. Imputation is a bookkeeping term meaning to put to the account. When believers truly believe Christ accomplished everything needed, God credits His righteousness to them, covering them.
Les explains that imputation is a bookkeeping term Paul uses throughout Romans, meaning to put to the account. God's righteousness is imputed to us and covers us because we have believed what He has done on our behalf. Les addresses the objection that belief does not seem to work, saying if we truly and honestly believe Christ accomplished everything that needed to be done, He moves right in and gives us the power to live a life pleasing in His sight. Believers will still fall and trip, but God is like a patient young mother who never gives up; He picks us up, says we are forgiven and cleansed, and tells us to move on. This applies to people genuinely concerned about dealing with God on His premises, not those merely fulfilling a ritualistic demand.