Satan actually works with,not against,G-d. Satan cannot do anything without G-d’s “green light”. In fact,Satan and the devil are two different entities.
Only G-d can have authority and power. Not Satan,not the devil,no one.
The references to Satan can be found in Jobs,Chronicles,Psalms and Zechariah. See Job 2:3-6,Zech.3:1-2 and Psalm 109:6-7.
Here are some very important verses from Isaiah which prove that G-d is the only one with power and authority:
I am the Eternal,and there is none else,there is no god beside me: I girded thee,though thou hast not known Me:That they may know the rising of the sun,and from the west,that there is none beside Me.I am the Eternal and there is none else.I form the light,and create darkness:I make peace and create evil: I the Eternal do all these things.[Isaiah 45:5-7].
The idea that Satan has G-d’s power and authority is not monotheism. It would mean that there is more than one G-d and there is not. Only G-d is G-d. Not Satan,not the devil,not a man,etc.
Satan is the Adversary. Satan does not work WITH God he works against God as the Adversary. God permits this, but this work and plan of Satan is not God's plan. God forbid!
Furthermore, scripture clearly shows that God permitted Satan to blind the minds of people. This demonstrates how strong an evil influence Satan has on the world and its people.
II Corinthians 4:4: In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.
In this passage Satan is referred to the god of this world. However, this is a title that Paul gives Satan in view of the fact that the true God is presently withholding the day of his wrath upon Satan's plan of evil in this world. Satan is not God, nor is he 'a god'. Nevertheless, the language Paul is using to describe Satan as the one engaged and propagating false gospels and 'other gospels' and blinding the mind to obscure the 'light of the glorious gospel of Christ' and distort the grace that 'shine unto them' from God's grace.