I spoke tonight on James 2, a tricky passage on the relationship between faith and works. It is the passage that infamously caused the young Martin Luther to label James 'the epistle of straw' (a view that he later rescinded) because he thought it threatened the doctrine of justification by faith alone through grace alone in Christ alone.
I came to the conclusion that when Paul is attacking ‘justification by works’ he is attacking the view that anything we do along with faith can be credited to us as righteousness; that it is only through faith in Jesus that anyone can obtain a ‘not guilty’ verdict when we become Christians. Works are not needed to receive justification. But when James affirms ‘justification by works’ he means that works are essential in the ongoing life of a Christian: they are how authentic faith shows itself. Works confirm and prove the reality of the faith which justifies. In that respect, faith without works cannot justify.
I found this vintage quote by CJ Mahaney perceptively clear and helpful in this context (particularly the bottom paragraph):
'Justification refers to a Christian’s position before God. The moment you were born again, God justified you. On the basis of Christ’s finished work, God thought of your sins as forgiven and declared that you were righteous.
Sanctification, on the other hand, refers to our practice before God. It is the ongoing process of battling sin and becoming more like Jesus. Though sanctification is the evidence and goal of our justification, we must never see it as the basis of our justification. Here’s where so many Christians get confused. They try to earn what has already been given to them as a free gift. As Martin Luther stated, “The only contribution we make to our justification is our sin which God so graciously forgives.”
There are other vital distinctions. Justification is about being declared righteous; sanctification is about becoming more righteous. Justification is immediate; sanctification is gradual. Justification is complete the moment God declares us righteous. It does not take place by degrees. Sanctification, however, is a process that lasts as long as we live. Finally, while every Christian enjoys the same degree of justification, we vary in terms of sanctification. You will never be more justified than you are at this moment, because justification is an act of God. But by God’s grace, you will become ever more sanctified as you cooperate with God’s Spirit in the process of change.
Though it’s important to distinguish between justification and sanctification, these two doctrines are inseparable. God does not justify someone without sanctifying him as well. Sanctification is not optional. If one has truly been justified, that will be evident by a progressive work of sanctification in his life.'
(From Why Small Groups?, pages 4-5)