I argue that the bishop of Hippo taught sola fide, declarative justification, and the divine acceptance of sinners based on faith alone although he presented these pre-Reformational thoughts with strong emphasis on the necessity of growth in holiness (sanctification). Victorinus and Ambrosiaster already taught a Reformational doctrine of justification prior to Augustine in the fourthcentury Latin Christianity. Therefore, the argument that sola fide and justification as an event did not exist before the sixteenth-century Reformation, and these thoughts were foreign to Augustine is not tenable. For Augustine, justification includes imputed righteousness by Christ’s work, which can be appreciated by faith alone and inherent righteousness assisted by the Holy Spirit at the same time of forgiveness in justification. Nonetheless, the sole ground of the divine acceptance does not depend on inherent righteousness, which is real and to increase. The salvation of the confessing thief and the remaining sinfulness of humanity after justification show Augustine that faith alone is the ground of God’s acceptance of sinners. Augustine’s relatively less frequent discussion of sola fide and declarative justification may be due to his need to reject the antinomian abusers who appealed to the Pauline understanding of justification even when they do not have any intentional commitment to holiness after their confessions. Augustine’s teaching on double righteousness shows considerable theological affinity with Bucer and Calvin who are accustomed to speak of justification in terms of double righteousness. Following Augustine, both Bucer and Calvin speak of the inseparability and simultaneity of justification and sanctification. Like Augustine, Bucer also maintains a conceptual, not categorical, distinction between the two graces of God in their doctrines of justification.