Romans 1:16-17 For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek. 17 For therein is the righteousness of God revealed from faith to faith: as it is written, The just shall live by faith.

Romans 1:16-17 are the key verses that summarised this epistle. The righteous shall live my faith. This righteousness of the believer is a gift from God that is appropriated by faith. It begins with faith and continues in faith, beginning to end.