2 The five porches in which the infirm folk lay signify the Law, which was first given to the Jews and to the people of Israel by Moses the servant of God. For this Moses the minister of the Law wrote five books. In relation therefore to the number of the books which he wrote, the five porches figured the Law. But because the Law was not given to heal the infirm, but to discover and to manifest them; for so says the Apostle, “For if there had been a law given which could have given life, verily righteousness should have been by the Law; But the Scripture has concluded all under sin, that the promise by faith of Jesus Christ might be given to them that believe;” therefore in those porches the sick folk lay, but were not cured.
For what says he? “If there had been a law given which could have given life.” Therefore those porches which figured the Law could not cure the sick. Some one will say to me, “Why then was it given?” The Apostle Paul has himself explained: “Scripture,” says he, “has concluded all under sin, that the promise by faith of Jesus Christ might be given to them that believe.” For these folk who were sick, thought themselves to be whole. They received the Law, which they were not able to fulfil; they learned in what disease they were, and they implored the Physician's aid; they wished to be cured because they came to know they were in distress, which they would not have known if they had not been unable to fulfil the Law which had been given.
For man thought himself innocent, and from this very pride of false innocence became more mad. To tame this pride then and to lay it bare, the Law was given; not to deliver the sick, but to convince the proud. Attend then, Beloved; to this end was the Law given, to discover diseases, not to take them away. And so then those sick folk who might have been sick in their own houses with greater privacy, if those five porches had not existed, were in those porches set forth to the eyes of all men, but were not by the porches cured.
The Law therefore was useful to discover sins, because that man being made more abundantly guilty by the transgression of the Law, might, having tamed his pride, implore the help of Him That pities. Attend to the Apostle; “The Law entered that sin might abound; but where sin abounded, grace has much more abounded.” What is, “The Law entered that sin might abound”? As in another place he says, “For where there is no law, there is no transgression.” Man may be called a sinner before the Law, a transgressor he cannot.
But when he has sinned, after that he has received the Law, he is found not only a sinner, but a transgressor. Forasmuch then as to sin is added transgression, therefore “has sin abounded.” And when sin abounds, human pride learns at length to submit itself, and to confess to God, and to say “I am weak.” To say to those words of the Psalm which none but the humbled soul says, “I said, Lord, be merciful unto me; heal my soul, for I have sinned against you.” Let the weak soul then say this that is at least convinced by transgression, and not cured, but manifested by the Law.
Hear too Paul himself showing you, both that the Law is good, and yet that nothing but the grace of Christ delivers from sin. For the Law can prohibit and command; apply the medicine, that that which does not allow a man to fulfil the Law, may be cured, it cannot, but grace only does that. For the Apostle says, “For I delight in the Law of God after the inner man.” That is, I see now that what the Law blames is evil, and what the Law commands is good. “For I delight in the Law of God after the inner man.
I see another law in my members resisting the law of my mind, and bringing me into captivity in the law of sin.” This derived from the punishment of sin, from the propagation of death, from the condemnation of Adam, “resists the law of the mind, and brings it into captivity in the law of sin which is in the members.” He was convinced; he received the Law, that he might be convinced: see now what profit it was to him that he was convinced. Hear the following words, “Wretched man that I am, who shall deliver me from the body of this death? The grace of God through Jesus Christ our Lord.”
Source: Sermons on Selected Lessons of the New Testament (New Advent)