omnes nervos in aliqua re contendere

Etymology:

• nervi properly = sinews, muscles, not nerves the existence of which was unknown to the ancients. Metaphorically nervi denotes not only strength in general but also specially—(1) vital power, elasticity, e.g. omnes nervos virtutis elidere (Tusc. 2. 11. 27), incīdere, to paralyse the strength of virtue; (2) motive power, mainspring, essence, of a thing, e.g. vectigalia nervi rei publicae sunt (Imp. Pomp. 7. 17), nervi belli pecunia (Phil. 5. 2. 15).