My bones are pierced in me - The bones are often represented in the Scriptures as the seat of acute pain; Psalm 6:2; Psalm 22:14; Psalm 31:10; Psalm 38:3; Psalm 42:10; Proverbs 14:30; compare Job 20:11. The meaning here is, that he had had shooting or piercing pains in the night, which disturbed and prevented his rest. It is mentioned as a special aggravation of his sufferings that they were "in the night" - a time when we expect repose.
And my sinews take no rest - See the word here rendered sinews explained in the note at ver. 3. The word literally means gnawers, and hence, the teeth. The Vulgate renders it, qui me comedunt, non dormiunt, "they who devour me do not slumber." The Septuagint, νευρά μον neura mou - my sinews, or arteries. Schleusner. Luther, "They who gnaw me." Coverdale, Sinews. I see no reason to doubt that the teeth or the jaws are meant, and that Job refers to the violent pain in the tooth, among the acutest pains to which the body is subject. The idea is, that every part of the body was diseased and filled with pain.

(m) My bones are pierced in me in the night season: and my sinews take no rest.
(m) Meaning sorrow.

My bones are pierced in me in the night season,.... Such was the force of his disease, that it pierced and penetrated even into his bones, and the marrow of them; and such the pain that he endured in the muscles and tendons about them, and especially in the joints of them, that it was as if all his bones were piercing and breaking to pieces; he was in a like condition the sick man is described in Job 33:19; and as David and Hezekiah were, Psalm 6:2; and what aggravated his case was, that this was "in the night season", when he should have got some sleep and rest, but could not for his pain: some render the words by supplying them thus; God, or the disease, or the pain, pierced my bones in the night season; or "the night pierced my bones from me"; so Mr. Broughton; but rather they may be rendered, and the sense be,
"in the night season everyone of my bones pierce "the flesh" that is upon me:''
his flesh was almost wasted and consumed, through the boil and ulcers on him, and he was reduced to a mere skeleton; and when he laid himself down on his bed, these pierced through his skin, and stuck out, and gave him exquisite pain:
and my sinews take no rest; being contracted; or his nerves, as the word in the Arabic language signifies, as is observed by Aben Ezra, Jarchi, Donesh, and others; which were loosened, and the animal spirits were sunk, and he so low and dispirited, that he could get no rest: or the pulsatile veins and arteries, as Ben Gersom and Elias Levita (a), in which the pulse beats, and which beats with less strength when persons are asleep than when awake; but such was the force of Job's disease, that it beat even in the night, when on his bed, so strongly, that he could take no rest for it; the pulse beats, as physicians say (b), sixty times in a minute, and double the number in a burning fever, and which might be Job's case. Some take the word in the sense of fleeing or gnawing (c), as it is used Job 30:3; and interpret it either of his enemies, who pursued after him, and had no rest in their beds, but went out in the night to inquire and hear what they could learn concerning him and his illness, whether it was become greater (d); or who devoured him by their calumnies and detractions, and could not sleep unless they did mischief to him; see Proverbs 4:16; or of the worms with which his body was covered, and which were continually gnawing, never rested, nor suffered him to take any rest; the Targum is, they that gnash at me rest not.
(a) In Tishbi, p. 67. So Lud. Capellus in loc. (b) Scheuchzer. Physic. Sacr. vol. 4. p 764. (c) "et rodentia mea", Schultens; "fugientia membra mea", so some in Michaelis. (d) Vid. Bar Tzemach in loc.

In the Hebrew, night is poetically personified, as in Job 3:3 : "night pierceth my bones (so that they fall) from me" (not as English Version, "in me"; see Job 30:30).
sinews--so the Arabic, "veins," akin to the Hebrew; rather, "gnawers" (see on Job 30:3), namely, my gnawing pains never cease. Effects of elephantiasis.