Job uses two sentences to think about what it would be like if he had never been born or had died at birth. (See: [[rc://en/ta/man/translate/figs-parallelism]] and [[rc://en/ta/man/translate/figs-euphemism]])
Job imagines something that could have happened in the past but which did not happen, as noted above. Alternate translation: "I should have been lying down quietly" (See: [[rc://en/ta/man/translate/figs-hypo]])
Here the word "rest" means to sleep peacefully, but also that Job would not be experiencing the pain that he does. (See: [[rc://en/ta/man/translate/figs-idiom]])