In his discussion on sanctification, Charles Hodge (d. 1878) nicely summarizes the Reformation position of faith, justification, sanctification, and good works. Here’s what Hodge says about the historical Protestant views (which are found in the Reformed Confessions, and ultimately Scripture):
First, it was universally admitted that good works are not necessary to our justification; that they are consequences and indirectly the fruits of justification, and, therefore, cannot be its ground.
Secondly, it was also agreed that faith, by which the sinner is justified, is not as a work, the reason why God pronounces the sinner just. It is the act by which the sinner receives and rests upon the righteousness of Christ, the imputation of which renders him righteous in the sight of God.
Thirdly, faith does not justify because it includes, or is the root or principle of good works; not as ‘fides obsequiosa’ [faith including evangelical obedience].
Fourthly, it was agreed that it is only a living faith, i.e., a faith which works by love and purifies the heart, that unites the soul to Christ and secures our reconciliation with God.
Fifthly, it was universally admitted that an immoral life is inconsistent with the state of grace; that those who willfully continue in the practice of sin shall not inherit the kingdom of God.
The Protestants, while rejecting the Romish doctrine of subjective justification, strenuously insisted that no man is delivered from the guilt of sin who is not delivered from its reigning power; that sanctification is in separable from justification, and that the one is just as essential as the other.