quos deus vult perdere prius dementat

Latin phrase

quos de·​us vult per·​de·​re pri·​us de·​men·​tat kwōs-ˈdā-u̇s-ˌwu̇lt-ˈper-de-ˌrā-ˌpri-u̇s-dā-ˈmen-ˌtät 

: those whom a god wishes to destroy he first drives mad