Sorcery :the use of power gained from the assistance or control of evil spirits especially for divining : necromancy. Merriam-Webster Dictionary
Sorcerer SOR'CERER, [L. sors, lot.] A conjurer; an enchanter; a magician. The Egyptian sorcerers corerntended with Moses.
Simon the Sorcer Acts 8:9-24
Act 8:9 Now a certain man [named] Simon had been in the city [Samaria] practicing magic and astonishing the people of Samaria, saying he was someone great.
Magic is the art of producing a desired effect or result through the use of incantation, ceremony, ritual, the casting of spells or various other techniques that presumably assure human control of supernatural agencies or the forces of nature.<Wikipedia.org>
Simon is commonly called "Simon Magus", for he was a magician, who had learned diabolical arts, and used enchantments and divinations, as Balaam and the magicians of Egypt did.
Act 8:10 To him people of all classes paid attention, declaring, "This man is the Power of God, known as the great Power." WNT They all exclaimed, “This man is the divine power known as the Great Power.”NIV.
Notes: That is, he is invested with it, and can command and use it. They certainly did not believe him to be God; but they thought him to be endued with a great supernatural power.A.C. The had followed this magician for years.
Act 8:12 But when Philip began to tell the Good News about the Kingdom of God and about the Name of Jesus Christ, and they embraced the faith, they were baptized, men and women alike.
Notes: Though they had been carried away so long with this deceiver, and had been so much attached unto him, and held in admiration of him; yet when Philip came and preached Christ unto them, such was the power that attended his ministry, and such the efficacy of divine grace that was exerted, that they not only gave heed unto him, but believed what he said: John Gill. May there be such power in the Preaching of the Kingdom of God and the Name of Jesus Christ today.
Act 8:13 Simon himself also believed, and after being baptized remained in close attendance on Philip, and was full of amazement at seeing such signs and such great miracles performed.
Notes: Simon himself also believed, and after being baptized remained in close attendance on Philip,that is, he believed that Jesus had performed miracles, and was raised from the dead, etc. All this he could believe in entire consistency with his own notions of the power of magic; and all that the connection requires us to suppose is that he believed this Jesus had the power of working miracles; and as he purposed to turn this to his own account, he was willing to profess himself to be his follower. It might have injured his popularity, moreover, if he had taken a stand in opposition when so many were professing to become Christians. People often profess religion because, if they do not, they fear that they will lose their influence, and be left with the ungodly. That Simon was not a real Christian is apparent from the whole narrative, Act_8:18, Act_8:21-23.
And when he was baptized - He was admitted to a “profession” of religion in the same way as others. Philip did not pretend to know the heart; and Simon was admitted because he “professed” his belief. This is all the evidence that ministers of the gospel can now have, and it is no wonder that they, as well Philip, are often deceived.Barnes Notes
1. Sorcery and Witch-craft are outlawed in the Bible. Gal 5:20, Deut 18:10 There shall not be found among you anyone who makes his son or his daughter to pass through the fire, or that uses divination, an observer of clouds, or a fortune-teller, or a witch,
1Sa_15:23 For rebellion is as the sin of witchcraft, and stubbornness is as iniquity and idol-worship. Because you have rejected the Word of Jehovah, He has also rejected you from being king!
2Ch_33:6 And he caused his sons to pass through the fire in the valley of the son of Hinnom. He also practiced secret arts, and used fortune-telling, and used witchcraft, and dealt with mediums, and with soothsayers. He did much evil in the sight of Jehovah in order to provoke Him to anger.
2. Simon Magnus was a deceiver. They are still to be found in the church and need to be exposed by the Gift of Discernment of spirits.