Isaiah 1:5-6

Why should you be beaten again,
    that you revolt more and more?
The whole head is sick,
    and the whole heart faint.
From the sole of the foot even to the head
    there is no soundness in it.
Wounds, bruises,
    and open sores;
they have not been closed,
    nor bandaged, nor soothed with oil.
Isaiah 1:5-6 Modern English Version (MEV)
 
Albert Barnes helps us delve into these verses in his Notes on the Bible:
 
Why ... - The prophet now, by an abrupt change in the discourse, calls their attention to the effects of their sins. Instead of saving that they had been smitten, or of saying that they had been punished for their sins, he assumes both, and asks why it should be repeated. The Vulgate reads this: ‘Super quo - on what part - shall I smite you anymore?’ This expresses well the sense of the Hebrew - על־מה ‛al-meh - upon what; and the meaning is, ‘what part of the body can be found on which blows have not been inflicted? On every part there are traces of the stripes which have been inflicted for your sins.’ The idea is taken from a body that is all covered over with weals or marks of blows, and the idea is, that the whole frame is one continued bruise, and there remains no sound part to be stricken. The particular chastisement to which the prophet refers is specified in Isa_1:7-9. In Isa_1:5-6, he refers to the calamities of the nation, under the image of a person wounded and chastised for crimes. Such a figure of speech is not uncommon in the classic writers. Thus Cicero (de fin. iv. 14) says, ‘quae hie reipublicae vulnera imponebat hie sanabat.’ See also Tusc. Quaes. iii. 22; Ad Quintum fratrem, ii. 25; Sallust; Cat. 10.
 
Should ye be stricken - Smitten, or punished. The manner in which they had been punished, he specities in Isa_1:7-8. Jerome says, that the sense is, ‘there is no medicine which I can administer to your wounds. All your members are full of wounds; and there is no part of your body which has not been smitten before. The more you are afflicted, the more will your impiety and iniquity increase.’ The word here, תכוּ tukû, from נכה nâkâh, means to smite, to beat, to strike down, to slay, or kill. It is applied to the infliction of punishment on an individual; or to the judgments of God by the plague, pestilence, or sickness. Gen_19:2: ‘And they smote the men that were at the door with blindness.’ Num_14:12: ‘And I will smite them with the pestilence.’ Exo_7:25: ‘After that the Lord had smitten the river,’ that is, had changed it into blood; compare Isa_1:20; Zec_10:2. Here it refers to the judgments inflicted on the nation as the punishment of their crimes.
 
Ye will revolt - Hebrew You will add defection, or revolt. The effect of calamity, and punishment, will be only to increase rebellion. Where the heart is right with God, the tendency of affliction is to humble it, and lead it more and more to God. Where it is evil, the tendency is to make the sinner more obstinate and rebellious. This effect of punishment is seen every where. Sinners revolt more and more. They become sullen, and malignant, and fretful; they plunge into vice to seek temporary relief, and thus they become more and more alienated from God.
 
The whole head - The prophet proceeds to specify more definitely what he had just said respecting their being stricken. He designates each of the members of the body - thus comparing the Jewish people to the human body when under severe punishment. The word head in the Scriptures is often used to denote the princes, leaders, or chiefs of the nation. But the expression here is used as a figure taken from the human body, and refers solely to the punishment of the people, not to their sins. It means that all had been smitten - all was filled with the effects of punishment - as the human body is when the head and all the members are diseased.
 
Is sick - Is so smitten - so punished, that it has become sick and painful. Hebrew לחלי lâchŏlı̂y - for sickness, or pain. The preposition ל denotes a state, or condition of anything. Psa_69:21. ‘And in (ל) my thirst, they gave me vinegar to drink.’ The expression is intensive, and denotes that the head was entirely sick.
 
The whole heart faint - The heart is here put for the whole region of the chest or stomach. As when the head is violently pained, there is also sickness at the heart, or in the stomach, and as these are indications of entire or total prostration of the frame so the expression here denotes the perfect desolation which had come over the nation.
 
Faint - Sick, feeble, without vigor, attended with nausea. Jer_8:18: ‘When I would comfort myself in my sorrow, my heart is faint within me;’ Lam_1:22. When the body is suffering; when severe punishment is inflicted, the effect is to produce landor and faintness at the seat of life. This is the idea here. Their punishment had been so severe for their sins, that the heart was languid and feeble - still keeping up the figure drawn from the human body.
 
From the sole of the foot ... - Or is we say, ‘from head to foot,’ that is, in every part of the body. There may be included also the idea that this extended from the lowest to the highest among the people. The Chaldee paraphrase is, ‘from the lowest of the people even to the princes - all are contumacious and rebellious.’
 
No soundness - מתם methôm, from תמם tâmam, to be perfect, sound, uninjured. There is no part unaffected; no part that is sound. It is all smitten and sore.
 
But wounds - The precise shade of difference between this and the two following words may not be apparent. Together, they mean Such wounds and contusions as are inflicted upon man by scourging, or beating him. This mode of punishment was common among the Jews; as it is at the East at this time. Abarbanel and Kimchi say that the word rendered here “wounds” (פצע petsa‛, a verbal from פצע pâtsa‛ to wound, to mutilate), means an open wound, or a cut from which blood flows.
 
Bruises - חבורה chabbûrâh. This word means a contusion, or the effect of a blow where the skin is not broken; such a contusion as to produce a swelling, and livid appearance; or to make it, as we say, black and blue.
 
Putrifying sores - The Hebrew rather means recent, or fresh wounds; or rather, perhaps, a running wound, which continues fresh and open; which cannot be cicatrized, or dried up. The Septuagint renders it elegantly πληγή φλγμαίνουσα plēgē flegmainous, a swelling, or tumefying wound. The expression is applied usually to inflammations, as of boils, or to the swelling of the tonsils, etc.
 
They have not been closed - That is, the lips had not been pressed together, to remove the blood from the wound. The meaning is, that nothing had been done toward healing the wound. It was an unhealed, undressed, all-pervading sore. The art of medicine, in the East, consists chiefly in external applications; accordingly the prophet’s images in this place are all taken from surgery. Sir John Chardin, in his note on Pro_3:8, ‘It shall be health to thy navel, and marrow to thy bones,’ observes, that the comparison is taken from the plasters, ointments, oils, and frictions, which are made use of in the East in most maladies. ‘In Judea,’ says Tavernier, ‘they have a certain preparation of oil, and melted grease, which they commonly use for the healing of wounds.’ Lowth. Compare the note at Isa_38:21.
 
Neither mollified with ointment - Neither made soft, or tender, with ointment. Great use was made, in Eastern nations, of oil, and various kinds of unguents, in medicine. Hence, the good Samaritan is represented as pouring in oil and wine into the wounds of the man that fell among thieves Luk_10:34; and the apostles were directed to anoint with oil those who were sick; Jas_5:14; compare Rev_3:18.
 
Ointment - Hebrew oil. שׁמן shemen. The oil of olives was used commonly for this purpose. The whole figure in these two verses relates to their being punished for their sins. It is taken from the appearance of a man who is severely, beaten, or scourged for crime; whose wounds had not been dressed, and who was thus a continued bruise, or sore, from his head to his feet. The cause of this the prophet states afterward, Isa_1:10 ff. With great skill he first reminds them of what they saw and knew, that they were severely punished; and then states to them the cause of it. Of the calamities to which the prophet refers, they could have no doubt. They were every where visible in all their cities and towns. On these far-spreading desolations, he fixes the eye distinctly first. Had he begun with the statement of their depravity, they would probably have revolted at it. But being presented with a statement of their sufferings, which they all saw and felt, they were prepared for the statement of the cause. To find access to the consciences of sinners, and to convince them of their guilt, it is often necessary to remind them first of the calamities in which they are actually involved; and then to search for the cause. This passage, therefore, has no reference to their moral character. It relates solely to their punishment. It is often indeed adduced to prove the doctrine of depravity; but it has no direct reference to it, and it should not be adduced to prove that people are depraved, or applied as referring to the moral condition of man. The account of their moral character, as the cause of their calamities, is given in Isa_1:10-14. That statement will fully account for the many woes which had come on the nation.