simul iustus et peccator!
“In historic Roman Catholic formulations, justification is not an eschatological reality because it hinges upon the believer’s good works (sanctification). A person is initially justified in baptism, and then through the infusion of habits and virtues, labor to become more just. The believer’s declaration of righteousness awaits the consummation, as God never declares a person righteous until he is actually righteous (author’s footnote). The Protestant position is strikingly different and visible in Luther’s aphorism simul iustus et peccator, ‘simultaneously righteous and sinner.'”
J.V. Fesko, Beyond Calvin: Union with Christ and Justification in Early Modern Reformed Theology (1517-1700), pg 96. Author’s footnote: “Canons and Decrees of the Council of Trent,” session 6, chps. 7-8, in Schaff, “Creeds of Christendom, 2.94-100.