The Righteousness of Christ as the Coat of Jacob

Calvin, in the Institutes, on Ambrose's assertion that we are covered by the righteousness of Christ in God's presence in the same way Jacob was covered by the skin of the animal in his father's presence, 3.11.23:

For this reason, it seems to me that Ambrose beautifully stated an example of this righteousness in the blessing of Jacob: noting that, as he did not of himself deserve the right of the first-born, concealed in his brother's clothing and wearing his brother's coat, which gave out an agreeable odor [Gen. 27:27], he ingratiated himself with his father, so that to his own benefit he received the blessing while impersonating another. And we in like manner hide under the precious purity of our first-born brother, Christ, so that we may be attested righteous in God's sight. Here are the words of Ambrose: "That Isaac smelled the odor of the garments perhaps means that we are justified not by works but by faith, since the weakness of the flesh is a hindrance to works, but the brightness of faith, which merits the pardon of sins, overshadows the error of deeds."

Quite an interesting typology. It had never occurred to me before.