Powers of darkness aim to seduce people to seek after secret knowledge that would give them a supernatural power. Of course, there is no such thing with God. The seeking of secret things leads people to the bondage of devil and into connections with the demons of darkness. The Good News of Jesus is revealed. All plans of God are revealed. Jesus and His apostles have given all necessary teachings. The door into the Kingdom of God is open.
God has no secret information that would benefit people. Instead of secret knowledge He has proclaimed openly the salvation work of Jesus and everyone is allowed to receive fully the benefits of the perfect sacrifice of Jesus. The more openly you proclaim Jesus, the more power you will have.
God's power flows into you in the unity and fellowship with Him. Your spirit is the receiver and your soul is the operator. You will be always dependent on His power and fellowship. God has designed you to be and operate in intimate relationship with Him. When you live and operate in the anointing of the Holy Spirit, you have reached the position, presence of Jesus, His guidance and authority. Then you are living and operating in His Name.
Jesus speaks here about the people, which He doesn't know. They do not belong to Him, because Jesus says that He knows His sheep. In the world there are a lot of people, who want supernatural powers or abilities, but they don't want to surrender their life unto Jesus. When they are trying to get contact with the supernatural powers they get into contact with deceiving demons of darkness.
All witches and magicians are deceived. There is no authority and godly power or healing miracle outside of Jesus. All "miracles" of witchcraft are full of lies. When the lies of witchcraft have defiled the soul, these people think that the works of deceiving spirits are true miracles. Denounce once and for all from this kind of things. Jesus will not recognize witches and magicians, although they claim to have performed things in His Name.
Jesus does not acknowledge the deeds that these people are boasting about. These people bring up their own deeds as a merit for salvation before the throne of God. Their actions prove that they are totally blind and arrogant, because they dare to boast like this even before Jesus in His Glory. They simply have no understanding about the salvation through the blood of Jesus and have not surrendered unto Him at all.
Jesus will give His Holy Spirit only for those who obey Him. Disobedience is a sin of witchcraft. Simon the Sorcerer (Acts 8) was an example about this kind of people. He did not surrender his heart to Jesus although he showed outward signs of a believer. He did not build on the rock, because he did not allow Jesus to come into his heart and make him a new creature.
We must never think Jesus would turn down any born again believer. Jesus absolutely knows every born again person, because His Spirit is in them. Every believer has the promise of the Holy Spirit to receive the anointing in order to operate in the Name of Jesus. If someone is operating differently than you are used to, do not criticize him. Recognize your own anointing and your mission which God has appointed to you. Be faithful in your own ministry and then you will have the crown of glory kept for you in Heaven.
Why didn't the evil spirit acknowledge the Name of Jesus in the mouth of the sons of Sceva? The answer is simple. Jesus said: "Without Me you can't do anything!" The sons of Sceva did not have any relationship with Jesus. They did not have the anointing of the Holy Spirit. They tried to deliver the demon possessed man in their own power. Jesus was not with them and they did not have the Holy Spirit.
The demons will acknowledge only the presence of Jesus in His anointed followers. They know exactly when a person has repented and renounced them. When you have cast out demons from your life by the power of the Holy Spirit and the blood of Jesus, they know you are God's own and thus their enemy. When you are filled with the Holy Spirit demons will see Jesus in you and they have to obey your commands everywhere. The demons are spirits of darkness and they can't stand the light and the Glory of Jesus. They have to flee when you command them in the Mighty Name of Jesus. Glory to God!
Jesus has called you to deliver people from the slavery of the evil spirits. Whenever you will face a person who is oppressed by the evil spirit, you will need just to ask advice from the Holy Spirit and act according to that. In the name of Jesus, you have permanent authorization and power to deliver people from the bondages of demons, whenever they want to become free.