How is witchcraft evil if it is spirituality in the purest sense?

Perhaps it is not.

It promotes sexual sin and draws us away from God.

When you seek to cast a spells upon people you seek to violate their liberty.  

Methinks you misinterpret witchcraft. Early on witches worked with the devil. They are known for their evil nature. They are not godly in any sense of the word. 

Galatians 5:20-21 KJV — Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies, Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God.

Who informed you that witchcraft is assultably evil?

This is absolutely not true, that is, if witchcraft is used to harm someone, he is evil!

If witchcraft is sometimes used to make someone perform at a curative level small pathologies that human science cannot do, he is good?

In any case, in both cases, witchcraft is a direct fight with the spirits of demons, reason why, whoever does it, will go to hell, without presenting the ID!!! CLEAR?

wishcraft is selfish.

it serves the user , and no one else.

satan is behind it.

facts...... https://www.lucistrust.org/books/about_alice_a_bai...

Because Degeneracy sucks.

Because it is the work of satan , that is why.