“Through him we have also obtained access by faith into this grace in which we stand, and we rejoice in hope of the glory of God.” -Romans 5:2
Through him: him being Jesus Christ, who was mentioned in the previous verse. Everything about our salvation depends on Jesus Christ. By signifying clearly to his readers upon whom their faith must rest, he dismisses altogether any possible alternative hope, like the merits of their works in the keeping of the Law of Moses.
Also, remarkable are the three movements of salvation in Pauline thought. Through faith in Jesus Christ we obtain access to grace, we stand in grace, and we rejoice in hope, specifically hope of the glory of God.
The word access here is quite significant. It is used in both sacred and pagan literature to refer to that one place (a gate or a port) where entry can be made on ground or shoreline that offeres no access to enemy forces. Think the gate of a fortress or the port of entry to country.
So it is by no other than Jesus Christ that we can enter into the grace in which once we enter, we now stand. The Greek word histemi translated stand in English has a wide spectrum of meaning (like the English word “cool”) so we must rely on the context and lexicons to discern the specific meaning. Here it means a condition or state of being.
Once we have obtained access to God’s grace through faith in Jesus Christ, we now stand in this grace. This standing refers to our spiritual condition, literally, our standing before God. This condition, by virtue of the kind of faith that saves (not the degree), is immutable. It does not shift or change with our feelings or our failings because the object of faith is one who is immutable, the second person of the Godhead, Jesus Christ.
Once we have obtained access into the fortress of God’s grace through the only gate, faith in Jesus Christ, we now stand righteous before God (remember our faith is imputed to us for righteousness), and we, therefore, rejoice—not in our own goodness or merits—in hope of the glory of God. Hope refers to the confidence we have in God’s promise. “Now faith is the assurance of things hoped for, the conviction of things not seen.” -Hebrews 11:1