For the righteousness of God is revealed in the gospel from faith to faith, just as it is written, “The righteous by faith will live.”
[Rom 1:17 NET]
A life of faith in Christ is as necessary to our present and experimental salvation, as his death upon the cross was to our past and actual salvation. If you are alive to what you are as a poor fallen sinner, you see yourself surrounded by enemies, temptations, sins, and snares; and you feel yourself utterly defenseless, as weak as water, without any strength to stand against them. Pressed down by the weight of unbelief, you see a mountain of difficulty before your eyes, sometimes in providence and sometimes in grace. You find, also, that your heart is a cage of unclean birds, and that in you, that is, in your flesh, there dwells no good thing; neither will nor power have you in yourself to fight or flee.
How then shall this mountain become a plain? How shall you escape the snares and temptations spread in your path? How shall you get the better of all your enemies, external, internal, infernal, and reach heaven’s gate safe at last? If you say, “By the salvation already accomplished,” are you sure that that salvation belongs to you? Where is the evidence of it, if you have no present faith in Christ? How can that past salvation profit you for present troubles unless there be an application of it? It is this application and manifestation of salvation which is being saved by his life (Rom. 5:10).
See how it works; and what a suitability is in it. You are all weakness, and he is and has all strength, which he makes perfect in your weakness. You are all helplessness against sin, temptation, and a thousand foes. But help is laid upon Christ as one that is mighty; he therefore sends you help from the sanctuary and strengthens you out of Zion (Psalm 20:2), that these sins and enemies may not get the better of you.