It's hard to beat Bavinck's careful, biblically-saturated, historically sensitive, no-more-longwinded-than-it-needs-to-be, warm-hearted theology. Here's some good stuff on faith in the course of moving from justification to sanctification.
Sinners are justified by faith alone. . . . The gratitude and joy that filled their hearts upon receiving all these benefits drove them to do good works before the thought that they had to do them even crossed their mind. For the faith by which they accepted these benefits was a living faith, not a dead one, not a bare agreement with historical truth, but a personal heartfelt trust in the grace of God in Christ Jesus. In justification that faith of course manifested itself only from its receptive side because in this connection everything depended on the acceptance of the righteousness offered and bestowed in Christ. Yet, from its very inception, and at the same time as it justified, it was also a living, active, and forceful faith that renewed people and poured joy into their hearts.
Actually, therefore, it was not faith that justified and sanctified, but it was the one undivided and indivisible Christ who through faith gave himself to believers for righteousness and sanctification, who is imputed and imparted to us on the part of God, and whom we therefore from the beginning possess in that faith as Christ for us and in us. From its very beginning, faith was two things at once: a receptive organ and an active force.
--Herman Bavinck, Reformed Dogmatics, 4:242-43; see also here