The story of the Gadarene demoniac (see Mark 5:1-20) is the worst case of demon possession recorded in the New Testament. No person was able to physically control this man, but spiritually he was no match for Jesus, who demonstrated his authority over demons. The term “demon possessed” is the English translation for the single Greek word daimonizomai (verb) or daimonizomenos (participle) – which is best transliterated as “demonized.”
To be “demonized” means to be under the control of one or more demons. The term never occurs in the Epistles, so we have no way of knowing how it would apply to believers in the Church Age. Possession implies ownership, and we do know that Satan and his demons cannot have or own a Christian who belongs to God. In that regard, as Christians, we possessed by the Holy Spirit. We have been purchased by the blood of the Lord Jesus Christ and we belong to Him. But that does not mean that we are not vulnerable. If we open the door to Satan’s influence, he will invade and claim squatter’s rights. He will resist eviction until the ground beneath him is removed through repentance and faith in God.
Another Greek phrase in the Gospels is echein daimonion, which means to “have a demon.” The religious leaders used this phrase when they accused both John the Baptist and Jesus of be being demonized (see Luke 7:33; John 7:20). The Pharisees made these accusations because they knew that John and Jesus’ supernatural knowledge had to have been communicated to them through some spiritual means. It was common in those days to have esoteric knowledge communicated by demons through human agents (mediums and spiritists). The Pharisees were unwilling to recognize Jesus as the Messiah, so they wrongly assumed that the source of his information was from demons instead of God.
Some people make the theological argument that the Holy Spirit and an evil spirit cannot coexist in a Christian in order to make the argument that Christians cannot be invaded by demons. However, that argument does not stand up for several reasons. First, Satan is the prince of this world and the “ruler of the kingdom of the air” (Ephesians 2:2). Thus, Satan and his demons are present in the atmosphere of this world, and so is the omnipresent Holy Spirit – which means they do coexist.
Second, Satan still has access to God the Father in heaven (see Revelation 12:10). Third, the Holy Spirit is in union – in coexistence – with our human spirit, and surely we don’t consider our human spirit perfect. Fourth, spatial arguments don’t apply to the spiritual realm, for there are no natural barriers or physical boundaries for spirits. This is why we shouldn’t think of a church building as a sanctuary. Our sanctuary is “in Christ,” not some physical, man-made structure. Fifth, if we are paying attention to a deceiving spirit, the spirit’s presence cannot be external only. The battle is in the mind.
If it were true that an evil spirit and the Holy Spirit could not operate at the same time and in the same sphere, there would be no need for the Bible to command us to be alert and put on the armor of God. The purpose of armor is to stop penetration, and that is for the protection of the believer, not the unbeliever.
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