By this answer Christ declared that he did not deliver any other rule of life than that which had formerly been delivered in the law of the Lord. Thus he both bore testimony to the divine law, that it was a doctrine of perfect righteousness, and at the same time met the calumnious charge of seeming, by some new rule of life, to incite the people to revolt from the law. The young man, who was not ill-disposed, but was puffed up with vain confidence, answers that he had observed all the precepts of the law from his youth. It is absolutely certain that he was immeasurably distant from the goal which he boasted of having reached. Had his boast been true, he would have wanted nothing of absolute perfection. For it has been demonstrated above, that the law contains in it a perfect righteousness. This is even obvious from the fact, that the observance of it is called the way to eternal life. To show him how little progress he had made in that righteousness which he too boldly answered that he had fulfilled, it was right to bring before him his besetting sin. Now, while he abounded in riches, he had his heart set upon them. Therefore, because he did not feel this secret wound, it is probed by Christ — “Go,” says he, “and sell that thou hast.” Had he been as good a keeper of the law as he supposed, he would not have gone away sorrowful on hearing these words. For he who loves God with his whole heart, not only regards everything which wars with his love as dross, but hates it as destruction (Philippians 3:8). Therefore, when Christ orders a rich miser to leave all that he has, it is the same as if he had ordered the ambitious to renounce all his honors, the voluptuous all his luxuries, the unchaste all the instruments of his lust. Thus consciences, which are not reached by any general admonition, are to be recalled to a particular feeling of their particular sin. In vain, therefore, do they wrest that special case to a general interpretation, as if Christ had decided that the perfection of man consists in the abandonment of his goods, since he intended nothing more by the expression than to bring a youth who was out of measure satisfied with himself to feel his sore, and so understand that he was still at a great distance from that perfect obedience of the law which he falsely ascribed to himself: I admit that this passage was ill understood by some of the Fathers; and hence arose an affectation of voluntary poverty, those only being thought blest who abandoned all earthly goods, and in a state of destitution devoted themselves to Christ. But I am confident that, after my exposition, no good and reasonable man will have any dubiety here as to the mind of Christ.
—John Calvin, Institutes, 4.13.13 (on Matthew 19:21, “Go, sell you have, and give it to the poor”)