Out of deference to the people who practice Wicca and who have written to me about this response, let me qualify it by saying that this is a combination of Biblical perspective and historical facts and the historical portions do not apply to each and every practicioner of Wicca.
_____________________________
Wicca Spells - What is Wicca?
What is Wicca and what are Wicca spells? While it is rooted in ancient pagan beliefs, the Wicca religion, as it is practiced now, is only about 50-years-old. Wicca is a belief system cobbled together in the 1940's and 1950's by Gerald Gardner from a variety of religious traditions and beliefs as well as Freemason rituals. Since Gardner published several books espousing his system of worship, many offshoots and variations of Wicca have sprung up.
There is no particular agreement between Wiccans, or "wise ones" concerning what they believe and worship. Some worship the "Goddess," some worship the "God," and some worship both. Others worship nature. Some Wiccans say they embrace Christian doctrine, while others reject it. Most promoters of Wicca believe in reincarnation.
One thing most Wiccans agree on is the fact that Satan is not a part of their pantheon and they vehemently deny Satan-worship as one of their practices. This is because they disavow the notion of moral absolutes. There is no such thing as good or evil, because it is all relative. Wiccans have only one law that they bind themselves to, called "The Rede." It simply states, "Do what ye will, harm ye none." In other words: "Do what ever you want to as long as no one gets hurt." The Three-fold Law governs consequences, and is a law of returns that states, "All good that a person does to another returns three-fold in this life; harm is also returned three-fold."
Wicca Spells - Mind Control
What about Wicca spells? Not all Wiccans practice witchcraft (which they call "magick" to set themselves apart from illusionists and magicians). Magick is to Wicca what prayer is to Christianity. Wiccans claim that the practice of magick is simply using their minds to control matter, while Christians call upon God to heal people and to intervene and work in their lives. Because the Rede forbids harming others and the Three-fold Law sets forth consequences for those who do, Wiccans view themselves as "white witches" or "nature witches."
Wicca is basically a religion that is about minding your own business and living peaceably with your neighbors and environment. Wiccans are eager to draw parallels between themselves and biblical Christianity for the sake of earning credibility, but what does the Bible have to say about this religion? You won't find the word "wicca" in the Bible, so let's evaluate the beliefs in light of what God says about them.
Wicca spells are idolism - Romans 1:25 says, "They exchanged the truth of God for a lie, and worshipped and served created things, rather than the Creator…" Who wants to settle for second best? In Isaiah 40, God paints a very cool picture of how much greater the Creator is than His creation. If you are worshipping anything besides the Creator, you are just spinning your wheels.
Wicca spells bring false hope - Hebrews 9:27 says, "…Man is destined to die once, after that, to face judgment." God says we get one chance at life, and that is it. There are no do-overs. If we don't accept God's gift of Jesus in our lifetime, He judges us as unwilling to be in His presence, and we are sent to Hell.
Wicca spells bring disillusionment - Mark 7:8 says, "You have let go of the commands of God and are holding on to the traditions of men". God is God, and we are not. We have a decision to make. Are we going to take God at His word and adopt His worldview, or not? Knowing God is hard work that takes a lot of discipline. Wicca is a religion that takes a pack of lies, ties it in a romantic ribbon, and searches out a well-intentioned, but lazy and gullible mark to sell its hollow doctrines.
Wicca spells bring rebellion - Deuteronomy 18:10-12 says, "Let no one be found among you who… practices divination or sorcery, interprets omens, engages in witchcraft, or casts spells…Anyone who does these things is detestable to the LORD..." Wicca witchcraft is a sin and God hates it. Why? Because it is an attempt to cut off our dependence on God and get answers apart from Him.
Wicca Spells - Separation from God
This is what sin is all about. Sin isn't just a heinous, socially disagreeable action. Sin is our decision to disagree with God on any topic - to rebel against Him. Sin is saying, "God, I want to live my life MY WAY." Romans 3:23 says, "For all have sinned and fallen short of the glory of God." Romans 6:23 says, "For the wages of sin is death…" This isn't bodily death, this is spiritual death: eternal separation from God and all the blessings that His presence brings. This is the definition of Hell: the absence of God's presence. That is what our sin buys for us.
Thankfully, Romans 6:23 doesn't end there. It goes on to say, "…but the gift of God is eternal life in Christ Jesus our Lord." God knew that we would all rebel in one way or another, and he provided a way for us to avoid that separation.