Can God and Unclean Spirits dwell in the same human being at the same time?
It would seem that the possibility does exist that both God and Unclean Spirits could dwell in a human being at the same time. According to Catholicism, this does not seem to be an issue.
It almost seems an impossibility but if we dive unto the subject matter a little more deeper, the reality seems to be yes.
God dwells with his saints. In this sense, we can say that Holy individuals are not only united to God, but in a mysterious way God dwells within them. God is united to their very being, their souls.
16Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you? 17If any man defile the temple of God, him shall God destroy; for the temple of God is holy, which temple ye are. - 1 Corinthians 3
We know two things about diabolical possessions.
1.) The Demon can only possess the body of a possessed person. The soul is not touched by the Devil.
2.) Saints and holy individuals can be possessed by the Demon, even though the individual never did anything to deserve to become possessed.
Thus we can see that a saint in total unity with God in their souls while they could be physically possessed by the Evil Spirits in their body!
Allow me to give an example. St. Mary of Jesus Crucified (5 January 1846 – 26 August 1876), a canonized saint was habitually united to God and suffered diabolical possession on at least two occasions. Throughout her torments Jesus was able to sustain her with his graces.
Amongst her graces were the stigmata, along with ecstasies, levitations that lasted for hours, bilocation, prophecies, the ability to read souls, the strange and unique phenomenon of being possessed by a good angel, and the transverberation of her heart.
She never left being truly united to God even when possessed. The Devil has a blind side!
St. Mary of Jesus Crucified: A beacon of holiness in the Arab world
St. Mariam of Jesus Crucified (Mariam Baouardy)
Other canonized saints have been diabolically possessed with God’s permission, just as Job was tempted by Satan with God’s permission!