The meaning and origin of the expression: Eye of newt and toe of frog, wool of bat and tongue of dog

Eye of newt and toe of frog, wool of bat and tongue of dog

What's the origin of the phrase 'Eye of newt and toe of frog, wool of bat and tongue of dog'?

This is the well-known incantation of the Three Witches in Shakespeare's Macbeth, 1605:

All:
Double, double toil and trouble;
Fire burn and cauldron bubble.

Second Witch:
Fillet of a fenny snake,
In the cauldron boil and bake;
Eye of newt, and toe of frog,
Wool of bat, and tongue of dog,
Adder’s fork, and blind-worm’s sting,
Lizard’s leg, and howlet’s wing,
For a charm of powerful trouble,
Like a hell-broth boil and bubble.

We now see the three witches' brew as a hocus-pocus spell, much imitated by spoof witches in comedies and hardly to be taken seriously. In Shakespeare's day the effect would have been rather different and he could have expected a significant proportion of the audience to have taken the magic potion storyline literally.

See other - phrases and sayings from Shakespeare.