My flesh is clothed with worms - Job here undoubtedly refers to his diseased state, and this is one of the passages by which we may learn the nature of his complaint; compare the notes at Job 2:7. There is reference here to the worms which are produced in ulcers and in other forms of disease. Michaelis remarks that such effects are produced often in the elephantiasis. Bochart, Hieroz. P. II, Lib. IV. c. xxvi. pp. 619-621, has abundantly proved that such effects occur in disease, and has mentioned several instances where death ensued from this cause; compare Acts 12:23. The same thing would often happen - and particularly in hot climates - if it were not for the closest care and attention in keeping running sores as clean as possible.
And clods of dust - Accumulated on the ulcers which covered his whole body. This effect would be almost unavoidable. Dr. Good renders this, "worms and the imprisoning dust," and supposes that the image is taken from the grave, and that the idea in the whole passage is that of one who is "dead while he lives;" that is, of one who is undergoing putrefaction before he is buried. But the more common and correct interpretation is that which refers it to the accumulated filth attending a loathsome disease; see Job 2:8. The word which is used here and rendered clods (גוּשׁ gûsh) means a lump of earth or dust. Septuagint, βώλακας γῆς bōlakas gēs; Vulgate, sordes pulveris," clods of earth." The whole verse is rendered by the Septuagint," My body swarms with the putrefaction of worms, and I moisten the clods of earth with the ichor (ἰχῶρος ichōros) of ulcers."
My skin is broken - - רגע râga‛. This word means, to make afraid, to terrify; and then to shrink together from fear, or to contract. Here it means, according to Gesenius, that "the skin came together and healed, and then broke forth again and ran with pus." Jerome renders it, aruit - dries up. Herder, "my skin becometh closed." Dr. Good, "my skin becometh stiff;" and carries out his idea that the reference here is to the stiffened and rigid appearance of the body after death. Doederlin supposes that it refers to the rough and horrid appearance of the skin in the elephantiasis, when it becomes rigid and frightful by the disease. Jarchi renders it, cutis mea corrugata - my skin is rough, or filled with wrinkles. This seems to me to be the idea, that it was filled with wrinkles and corrugations; that it became stiff, fixed, frightful, and was such as to excite terror in the beholder.
And become loathsome - Gesenius, "runs again with pus." The word here used מאס mâ'as means properly to reject, contemn, despise. A second sense which it has is, to melt, to run like water; Psalm 58:7, "Let them melt away (ימאסוּ yı̂mâ'asû) as waters." But the usual meaning is to be preferred here. His skin became abhorrent and loathsome in the sight of others.

My flesh is clothed with worms - This is perhaps no figure, but is literally true: the miserably ulcerated state of his body, exposed to the open air, and in a state of great destitution, was favorable to those insects that sought such places in which to deposit their ova, which might have produced the animals in question. But the figure is too horrid to be farther illustrated.
Clods of dust - I believe all the commentators have here missed the sense. I suppose Job to allude to those incrustations of indurated or dried pus, which are formed on the tops of pustules in a state of decay: such as the scales which fall from the pustules of the smallpox, when the patient becomes convalescent. Or, if Job's disease was the elephantiasis, it may refer to the furfuraceous scales which are continually falling off the body in that disorder. It is well known, that in this disease the skin becomes very rigid, so as to crack across, especially at the different joints, out of which fissures a loathsome ichor is continually exuding. To something like this the words may refer, My Skin is Broken, and become Loathsome.

My flesh is (c) clothed with worms and clods of dust; my skin is broken, and become loathsome.
(c) This signifies that his disease was rare and most horrible.

My flesh is clothed with worms and clods of dust,.... Not as it would be at death, and in the grave, as Schmidt interprets it, when it would be eaten with worms and reduced to dust; but as it then was, his ulcers breeding worms, or lice, as some (y); these spread themselves over his body: some think it was the vermicular or pedicular disease that was upon him, and the scabs of them, which were all over him like one continued crust, were as a garment to him; or those sores of his, running with purulent matter, and he sitting and rolling himself in dust and ashes, and this moisture mingling therewith, and clotted together, formed clods of dust, which covered him all over; a dismal spectacle to look upon! a precious saint in a vile body!
my skin is broken: with the boils and ulcers in all parts, and was parched and cleft with the heat and breaking of them:
and become loathsome; to himself and others; exceeding nauseous, and extremely disagreeable both to sight and smell: or "liquefied" (z); moistened with corrupt matter flowing from the ulcers in all parts of his body; the word in Arabic signifies a large, broad, and open wound, as a learned man (a) has observed; and it is as if he should say, whoever observes all this, this long time of distress, night and day, and what a shocking figure he was, as here represented, could blame him for wishing for death in the most passionate manner?
(y) So Sephorno and Bar Tzemach. (z) "liquefit", Junius & Tremellius; "colliquefacta est", Piscator, Mercerus. (a) Hinckelman. Praefat. ad Alcoran. p. 30.

In elephantiasis maggots are bred in the sores (Acts 12:23; Isaiah 14:11).
clods of dust--rather, a crust of dried filth and accumulated corruption (Job 2:7-8).
my skin is broken and . . . loathsome--rather, comes together so as to heal up, and again breaks out with running matter [GESENIUS]. More simply the Hebrew is, "My skin rests (for a time) and (again) melts away" (Psalm 58:7).

Worms - Which were bred out of Job's corrupted flesh and sores. Dust - The dust of the earth upon which he lay. Broken - By ulcers in all parts of it.