It is characteristic of faith to reckon on God, not simply in spite of difficulty, but in spite of impossibility.
Faith does not concern itself about means; it counts upon the promise of God. To the natural man, the believer may seem to lack prudence; nevertheless, from the moment it becomes a question of means which render the thing easy to man, it is no longer God acting; it is no longer His work where means are looked to. When with man there is impossibility, God must come in, and it is so much the more evidenced to be the right way, since God only does that which He wills.
Faith has reference to His will, and to that only; thus it consults neither with means nor with circumstances. In other words, it consults not with flesh and blood. Where faith is weak, external means are beforehand reckoned on in the work of God. Let us remember that when things are feasible to man, there is no longer need of the energy of the Spirit. Christians do much, and effect little—why?
In Hebrews, faith is looked upon as an active principle of endurance and conduct, reliance on God's Word through grace for practice.
Romans presents the principle on which we are justified in virtue of Christ's work, the ground of peace. This principle is the non-working faith of the sinner. The book of Hebrews highlights, rather, the active-working faith of the saint. J.T. Armet