Moon Magic Explained

The full moon has been associated with magic and witches for millennia. The ancient Roman writer, Horace, made a reference to a witch drawing the moon down out of the sky.
Horace (Epode 17)—says the Witch Canidia “… must I, who can move waxen images and draw down the moon from the sky by my spells, who can raise the vaporous dead, and mix a draught of love lament the effect of my art, availing nothing upon you?”
Margot Adler’s Drawing Down the Moon, has a picture from a Greek vase, supposedly from the

Ancient lunar magic on vase.
second century BCE. This depiction has some Greek lettering near both of the figures. The word on the left is translated as, “beautiful.” The words on the right apparently translates as, “who [are] of the moon mistress.”

Werewolves famously shape-shift during the full moon, and the cult of the werewolf has ties to the ancient witch-cult. Essentially, the full moon was a time to use the moon’s power to enhance shamanic shape-shifting work.

In Aradia, The Gospel of the Witches Aradia, the holy daughter of Diana, left these instructions to her followers:
Whenever you have need of anything, once in the month when the Moon is full, then shall you come together at some deserted place, or where there are woods, and give worship to She who is Queen of all Witches. Come all together inside a circle, and secrets that are as yet unknown shall be revealed.
The traditional use of the phases of the moon for magic are as follows:
The new moon is the most auspicious time for banishing and neutralizing spells.
The days of and around the crescent moon are the most powerful time to work spells for growth and beginnings, which should manifest at the Full Moon.
The waxing moon is the best time to do a spell for growth, beginning new projects, initiation and enhancement.
The days of and around the gibbous moon are the most powerful time for spells of fruition and completion
The Moon looks full in the sky for two or three nights, and each of them are excellent for magic that depends on power flowing at its peak.
During the waning Moon, do spells to banish evil influences, lessen or remove obstacles and illness, neutralize enemies, scry, divine, and to remove harm. These influences become stronger as the moon darkens.