Bruce really sounds close to Luther here.
“God pronounces a man righteous at the beginning of his course, not at the end of it. If he pronounces him righteous at the beginning of his course, it cannot be on the basis of works which he has not yet done; such justification is, on the contrary, ‘an act of God’s free grace, wherein he pardoneth all our sins, and accepteth us as righteous in his sight’ (Westminster Shorter Catechism).
And when it comes to the question of our acceptance by God, how much more satisfying it is to know oneself ‘justified freely by his grace’ than to hope to be justified by ‘the deeds of the law.’ In the latter case, I can never be really satisfied that I have ‘made the grade,’ that my behaviour has been sufficiently meritorious to win the divine approval. Even if I do the best I can (and the trouble is, I do not always do that), how can I be certain that my best comes within measurable distance of God’s requirement? I may hope, but I can never be sure. But if God in sheer grace assures me of his acceptance in advance, and I gladly embrace his assurance, then I can go on to do his will without always worrying whether I am doing it adequately or not. In fact, to the end of the chapter I shall be an ‘unprofitable servant,’ but I know whom I have believed: ‘He owns me for his child; I can no longer fear.'”
F. F. Bruce, The Epistle of Paul to the Romans(Grand Rapids: Eerdmans, 1963), 102-3.