These words can be translated in active form. Alternate translation: "Someone who is patient can persuade a ruler" or "Someone who is patient can speak to a ruler and change his mind" (See: [[rc://en/ta/man/jit/figs-activepassive]])
The word "tongue" is a metonym for the words the person speaks using the tongue. The word "bone" is a metaphor for strong opposition. Alternate translation: "gentle speech can overcome strong opposition" (See: [[rc://en/ta/man/jit/figs-metaphor]])