John Donne’s or who cleft the Devil’s foot, Teach me to hear mermaids singing, Or to keep off envy’s stinging means that there is no way one can get a chaste woman in this world. The first part, “Or who cleft the Devil’s foot”, emphasizes how getting a virtuous woman is as easy or difficult as clinging on the devil’s foot. It is impossible to get hold of the devil; consequently, it is impossible to get a chaste woman.
The second part, “teach me to hear mermaids singing”, still explores whether it is possible to get a virgin woman. The writer compares hearing mermaids sing to getting a pure woman. It is impossible to learn how to hear ghosts sing. Finally, the sting of envy is inevitable; if it were possible to keep off this sting, then one would possibly find a chaste woman.