First, let's define Satanism. I found a help article, so read it HERE. The article says that there are various definitions of Satanism:
...there is a plethora of ideologies and false philosophies in Satanism. You can be hard pressed to find a handful outside their own coven, church, or group that “believe” the same way. Some of Satanism's practices are constant, but Satanists' comfort and unity is found more in the “acts” of rituals than in the “relationship” to a belief system. It is easier to call themselves "Satanists" if they “do” certain things.
Even in their harsh disagreement of principles and beliefs, there is an underlying commonality: self. The very sin for which Satan was forever dismissed from God’s presence is their common denominator: selfishness. All forms of Satanism claim that life exists to consume. Wicca demands you treat mother earth with respect and use the power that is within her and yourself, but for your own good. Devil worshippers hail allegiance to Satan and think he will guard them for all eternity; that is, if they believe there is an eternity. Some adherents of Satanism hold that the only existence they will ever know is here on earth. And thus, devil worshippers live for the moment and their creed is gluttony and debauchery.
In short, Satanism, while it may or may not be worshiping Satan, is a conscious effort to NOT worship the one true real God. Romans 1 gives a clear look into the heart and motives of a Satanist. They have “depraved minds to do what ought not to be done. They have become filled with every kind of wickedness” (vv 28-29).
Will God still help those under control of Satanism?
If you are asking whether God will help someone "possessed" by a demon, then YES, God will help. Consider the times when Jesus saved demon-possessed people.
[Read this post about spiritual warfare and how Christians are to fight against demons and their influence]
If you are asking whether God will help a person is not possessed by a demon, but worships Satan, then YES, God will help. After all, God wants people to be saved including those involved in forms of the occult. Yet there is a degree of human responsibility in salvation. Acts 2:21 says: "And it shall come to pass that everyone who calls upon the name of the Lord shall be saved." In order to be saved, a person must repent of his sin and call for God's help on his own accord. God may open the spiritual eyes of a person under the control of Satanism, but he must embrace this truth for himself. In other words, if a person is under the control of Satanism and resists God's help, God will not force this choice onto a person, even if it is for their own good.
[Answered by Pastor HM]
