"I am just skin and bones" or "My skin sticks to my bones." Job speaks of his bones, skin, and flesh to describe his appearance. He was extremely thin, and people could easily see the shape of his bones. Some languages have idioms for this.
This idiom means that he is barely surviving, that he almost does not survive. Alternate translation: "I am barely alive" or "I hardly survive" (See: [[rc://en/ta/man/translate/figs-idiom]])