Clavam extorquere Herculi.

Would you attempt to wrest his club from the hands of Hercules? may be said to any one undertaking what is much beyond his capacity to perform. Such was anciently the reverence paid to Homer, that to imitate his verses was thought to be as difficult as to take by force his club from Hercules, or the thunderbolt from the hands of Jupiter. The adage may also be applied to any one entering into a contest with persons superior to him in fortune and power. You may as well take a bear by the tooth.«He that meddleth with strife that doth not belong to him, is like one that taketh a mad dog by the ear».