The doctrine of justification is itself not the gospel. The gospel is the message concerning what God has done through Christ to deal with the effects of human sin (cf. 1 Cor. 15:1-4) and to liberate humanity and the whole creation from the effects of sin (cf. [Rom] 8:19-24). Those who believe the gospel and give their allegiance to his son God justifies, that is declares them to be right. They enjoy the status of those for whom God has made a favorable adjudication. (200)
-Colin Kruse (Pillar NT Commentary on Romans)
CWoznicki Think Out Loud 