Here "I am in the right" means I am the one who has done right things. Alternate translation: "Although I have done right things" or "Even though I am innocent" (See: [[rc://en/ta/man/jit/figs-idiom]] and [[rc://en/ta/man/jit/figs-nominaladj]])
Here "mouth" represents Job's words. Alternate translation: "my own words would accuse me" or "what I say would condemn me" (See: [[rc://en/ta/man/jit/figs-metonymy]])
Here "my words" are spoken of as if they could take action. Alternate translation: "God would use what I say to prove me guilty" (See: [[rc://en/ta/man/jit/figs-metaphor]])