…The lawyer, accustomed to the persuasion of law righteousness, blinded himself with confidence in works. Then he sought only what were works of righteousness whereby salvation is acquired. Therefore he is rightly sent back to the law wherein there is a perfect mirror of righteousness.
With a clear voice we too proclaim that these commandments are to be kept if one seeks life in works. And Christians must know this doctrine, for how could they flee to Christ unless they recognized that they had plunged from the way of life over the brink of death? How could they realize how far they had wandered from the way of life unless they first understood what that way is like? Only, therefore, when they distinguish how great is the difference between their life and divine righteousness that consists in accepting the law are they made aware that, in order to recover salvation, their refuge is in Christ.
To sum up, if we seek salvation in works, we must keep the commandments by which we are instructed unto perfect righteousness. But we must not stop here unless we wish to fail in mid-course, for none of us is capable of keeping the commandments. Therefore, since we are barred from law righteousness, we must betake ourselves to another help, that is, to faith in Christ. For this reason, as the Lord in this passage recalls to the law a teacher of the law whom he knew to be puffed up with empty confidence in works, in order that he may learn he is a sinner, subject to the dreadful judgment of eternal death, so elsewhere he comforts with the promise of grace without any mention of the law others who have already been humbled by this sort of knowledge: “Come to me all who labor and are heavy-laden, and I will refresh you… and you will find rest for your souls”
—John Calvin, Institutes, 3.18.9 (Battles edition)