I'm trying to figure out these days the precise nature of the relationship between the gospel and growth, or justification and sanctification, or status and progress, in the Christian life. In listening to a DMin class taught by Edmund Clowney and Tim Keller (available in full for free at iTunes) I've been alerted to Berkouwer's statements that sanctification is not graduating from but leaning into our justification.
I have been very helped by this and I think it is right. We grow not by moving on from the gospel of grace but by ever deeper reflection on it, on that same good news that got us in. When confronting Peter's racism, Paul did not tell him to have longer quiet times but that his conduct was "not in step with the truth of the gospel" (Gal 2:14).
What is not mentioned in the DMin class is that Berkouwer, along with other strands of continental Reformed thought, neglected (some say denied) the new ethical impulse implanted in the soul in regeneration. See Berkouwer's Faith and Sanctification (Eerdmans, 1952) for his full exploration of these things.
All this is to say that I've found Carl Henry's treatment of the relation between justification and sanctification very helpful. In Personal Christian Ethics (Eerdmans, 1957), he interacts with Berkouwer but sides rather with Charles Hodge and John Murray, who emphasize that while sanctification must assuredly be by faith (no less than justification is by faith), nevertheless in sanctification there is implanted a new impulse so that, though sin is not eradicated in this life, it will not reign in the life of a true believer (pp. 467-71; see also 370-77). I have found this in Edwards too.
So I continue to think about how the gospel is not just the ticket in, to be torn up once we're in, but the very air we are to breathe after we're in.