My bones are pierced in me - The bones are often represented in the Scriptures as the seat of acute pain; Psalms 6:2; Psalms 22:14; Psalms 31:10; Psalms 38:3; Psalms 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.