We love to tout the expression that we are “saved by grace through faith” (Eph 2:8-9). And we are emboldened at the fact that we are made right with God “through faith” (Rom 5:1). Noah is an example of a life of faith that goes far beyond merely acknowledging something to be true. Noah is an example of what real saving faith looks like. A faith that believes God and responds accordingly, faith that obeys God.
By faith Noah, being divinely warned of things not yet seen, moved with godly fear, prepared an ark for the saving of his household, by which he condemned the world and became heir of the righteousness which is according to faith.” (Hebrews 11:7, NKJV)
(Barnes’ New Testament Notes) It is observable here, that it is not said that Noah had specific faith in Christ, or that his being made heir of the righteousness of faith depended on that, but it was in connection with his believing what God said respecting the deluge. It was faith or confidence in God, which was the ground of his justification, in accordance with the general doctrine of the Scriptures that it is only by faith that man can be saved, though the specific mode of faith was not that which is required now under the gospel. In the early ages of the world, when few truths were revealed, a cordial belief of any of those truths showed that there was real confidence in God, or that the principle of faith was in the heart; in the fuller revelation which we enjoy, we are not only to believe those truths, but specifically to believe in Him who has made the great atonement for sin, and by whose merits all have been saved who have entered heaven. The same faith or confidence in God which led Noah to believe what God said about the deluge would have led him to believe what he has said about the Redeemer; and the same confidence in God which led him to commit himself to his safe keeping in an ark on the world of waters, would have led him to commit his soul to the safe keeping of the Redeemer, the true Ark of safety. As the principle of faith, therefore, existed in the heart of Noah, it was proper that he should become, with others, an “heir of the righteousness by faith.”
I love the balance the Apostle Paul presents when in context he shows us how real faith and real righteousness looks in the life of a believer.
For by grace, you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast. For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand that we should walk in them.” (Ephesians 2:8–10, NKJV)