It's certainly tempting to just immediately say 'No, of course witches don't believe in the devil!' But today I'd like to take the time to think deeply about this question and I don't think the answer is as clear cut as many would suggest. To begin with, not all witches believe in the divine or would consider themselves religious. To me, witchcraft is a practice or something you do and as such it can be completely void of any belief in the divine. And if you choose to perform witchcraft without the addition of divine energy than of course the answer would be irrelevant as the devil is Christian religious entity.
There are, however, many witches who do channel divine power for their witchcraft practice. Sometimes this may include calling upon the power of the Goddess and the God. The god in this case is sometimes called the Green Man or the Horned one and can appear as a satyr type figure with horns or hooves. This archetype is inspired by pre-christian gods like the Greek God Pan or the Celtic God Cernunnos. This pagan God rules over the wild energy of the forest, our own human sexuality, and is a manifestation of the masculine energy in the world. Like many pagan Gods, he is neither good nor bad as Pagan societies did not view their religious figures in a rigid binary system.
When Christianity came to Europe it viewed chastity and modesty being righteous and sexual freedom as being immoral. So naturally, this put figures like Pan and Cernunnos in a difficult spot. Over time Christians overlaid their own story of the Devil with the much older masculine archetypes of pre-christian Gods, which is why the Devil often looks like the Greek God Pan. This is why it’s so difficult to say if witches work with the energy of the Devil. If a witch is calling upon the divine masculine energy of the wild, are they working with the Devil?
To complicate matters further, there are also some witches to do work with the Christianized concept of the Devil as opposed to the Pagan masculine archetype. Some believe that the Devil represents the very embodiment and power of witchcraft. In Christianity the Devil is connected with things such as ecstatic pleasure, celebrations, feasting, and unbridled revelry. These are things that are often connected to various witchcraft traditions. This concept of the Devil is still somewhat removed from the character of Satan - the one who casts evil doers into the fiery realms of hell. So in that way, you could say that yes, some witches do celebrate the wild and unpredictable power of the ‘Devil’, but not the fire and brimstone figure that is Satan.
On the other end of the spectrum, there are many witches that do not work with the wild masculine energy at all. There are some groups, like the Dianic witches, who focus more on the Goddess and the ideas of the sacred feminine. There are also groups that work with a much more watered down version of the sacred masculine that is very much removed from the idea of the Devil. So once again I leave you to determine the direction of your own spiritual path and which, if any, divine forces you will choose to work with in your witchcraft practice.
So, to conclude, I think this question is more complicated and I don't believe a 'yes' or 'no' answer would suffice. To practice witchcraft requires a thinking beyond the binary of Good vs. Evil (or God vs. Devil) to which most belief systems are based.
Unlike the Abrahamic traditions, Witchcraft is not based upon a strict division of what is good and what is evil. Witches use nature to fuel their concept of the divine and in the world of nature there is no battle between good and evil. A lion is not ‘evil’ because it kills the gazelle, and a deer is not ‘good’ because it eats only plants. Nature is both cruel and beautiful at the same time. Likewise, witchcraft can be used for both positive and malevolent gains.
With witchcraft there is no governing body or official rule book telling you what you can and cannot do. Witchcraft is not something that was invented and controlled - it has always existed. The power of witchcraft lays within the plants, the moon, the stars, and ourselves. Witches over time learned to tap into this natural power and created spells for what they needed help with in their day to day lives. There have been many witches that have cast curses against others from time to time and there have been many that have dedicated their craft to healing and helping others. There are some witchcraft traditions, like Traditional Witchcraft, that are not morally opposed to hexes and will perform them if a significant need arises. There are also some belief structures, like Wicca, where most of the followers are very much morally opposed to casting hexes and curses.
How you choose to perform witchcraft is entirely up to you, and the moral consequences of those actions will likewise lie entirely on your own shoulders. Witchcraft respects that you are an individual, capable of defining and establishing your own sense of morality and justice.
What are your thoughts on this? I'd love for fellow witches to share their thoughts in the comments section. Do my ideas resonate with you or am I way off the mark?