The lunar tradition

The Sun and the Moon are both very important in symbolism and magic.
The Moon representing the feminine principle and the Sun, the masculine principle, and all its virtues and defaults are in relation to this principle; passivity, moist, cold, imagination, intuition, fecundity,  growth, occult energy.

The lunar cult is very ancient and is the celestial body which has always inflamed the imagination of man because of its mysterious path, resembling no other, it's always changing aspect following its cycle, disappearing completely once each month, luminous but only reflecting a light that is not its own.
The Moon has always personified the great goddesses Isis of the Egyptians, Astarte of the Phenicians, Cybele of the Phrygians, Selena and Artemis of the Greeks, the Romans Diana, the Arab Alilat, the Celts Belisana, all these goddesses have a very strong connection to the Moon.

So the Moon can be seen as positive as well as negative. It symbolises cyclic renewal or rebirth, fertility but also madness and death.

The most important aspect of the Moon related to magic comes from the influence of the Moon upon nature, the plant kingdom, towards birthing, as well as the mood of the living beings on Earth.

The fact that the domain of the Moon being the night, darkness and spirits, especially when it was full, exalted the maleficent works. That's why the night has become the domain of witchcraft.