The Tuscan legend of Aradia, daughter of the
moon goddess Diana who was dispatched to earth to
establish witchcraft and teach it to witches, was published
by the American folklorist, Charles Godfrey
Leland, in 1889. Leland said the legend had been
passed on to him by a hereditary Etruscan witch named
Maddalena. Godfrey said the name Aradia is a corruption
of Herodias, or Queen Herodias, the wife of Herod,
with whom Diana came to be identified by the 11th
century.
Leland went to Tuscany in northern Italy in the 1880s.
There he met a “sorceress” named Maddalena, whom he
employed to collect from her witch “sisters” old spells
and traditions. In 1886, he heard about a manuscript that
supposedly set down the old tenets of witchcraft. He told
Maddelana to find it. A year later, she gave him a document
in her own handwriting, an alleged copy of this
manuscript.
Leland translated it into English and published it as
Aradia, or the Gospel of the Witches. He was struck by the
references to Diana and Lucifer, and offered it as evidence
of witchcraft as an old religion. In his preface, he
acknowledged drawing from other, unspecified sources.
He never produced Maddalena or any documentation to
verify her existence.

Aradia recounts the story of Diana’s daughter and of
Diana’s rise to become Queen of the Witches. Diana is
created first among all beings and divides herself into
light and darkness. She retains the darkness and makes
the light into Lucifer (whose name means “light-bearer”),
her brother and son. She falls in love with him and seduces
him by changing herself into a cat. Their daughter
from that union, Aradia, is destined to become “the Messiah
of witches.” Aradia lives for a while in heaven and
then is sent to earth by Diana to teach the arts of witchcraft,
especially poisoning and malevolent acts against
“oppressors”:

And thou shalt be the first of witches known;
And thou shalt be the first of all i’ the world;
And thou shalt teach the art of poisoning,
Of poisoning those who are the great lords of all;
Yea, thou shalt make them die in their palaces;
And thou shalt bind the oppressor’s soul (with power);
And when ye find a peasant who is rich,
Then ye shall teach the witch, your pupil, how
To ruin all his crops with tempests dire,
With lightning and with thunder (terrible),
And with the hail and wind …
And when a priest shall do you injury
By his benedictions, ye shall do to him
Double the harm, and do it in the name
Of me, Diana, Queen of witches all!
When Aradia’s task is finished, Diana recalls her
daughter to heaven and gives her the power to grant the
desires of the meritorious witches who invoke Aradia.
Such requests include success in love, and the power to
bless friends and curse enemies, as well as:

To converse with spirits.
To find hidden treasures in ancient ruins.
To conjure the spirits of priests who died leaving treasures.
To understand the voice of the wind.
To change water into wine.
To divine with cards.
To know the secrets of the hand [palmistry].
To cure diseases.
To make those who are ugly beautiful.
To tame wild beasts.

The invocation for Aradia is given as follows:
Thus do I seek Aradia! Aradia! Aradia! At midnight,
at midnight I go into a field, and with me I bear water,
wine, and salt, I bear water, wine, and salt, and my talisman—
my talisman, my talisman, and a red small bag
which I ever hold in my hand—con dentro, con dentro,
sale, with salt in it, in it. With water and wine I bless
myself, I bless myself with devotion to implore a favor
from Aradia, Aradia.