The Greek word translated as "torment" in Revelation 9 is basanizo (Strong’s #928):
Revelation 9:5 And to them it was given that they should not kill them, but that they should be tormented five months: and their torment was as the torment of a scorpion, when he striketh a man.
6 And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them
Basanizo is a word that does not mean to torture as some would think. Instead, basanizo (torment) is a word that means to frustrate and to trouble.
The Greek word basanizo is also translated as "toiling":
Mark 6:47 And when even was come, the ship was in the midst of the sea, and he alone on the land.
48 And he saw them toiling in rowing; for the wind was contrary unto them: and about the fourth watch of the night he cometh unto them, walking upon the sea, and would have passed by them.
Again, basanizo, the word translated as "torment" in Revelation 9 is translated as "toiling" in the verse above. Obviously, it would have been very frustrating for the disciples as they toiled in rowing their boat against strong waves going in the opposite direction. Frustrating, and troubling, but not tortuous.
Basanizo is also translated as “vexed” in this verse:
2 Peter 2:7 And delivered just Lot, vexed (#2669) with the filthy conversation of the wicked: 8 (For that righteous man dwelling among them, in seeing and hearing, vexed (#928) his righteous soul from day to day with their unlawful deeds;)
The word we’re looking for is in verse 8 wherein God tells us that Lot’s righteous soul was “vexed” on a daily basis by the unlawful (sinful) deeds of the wicked. Since God’s elect have all had a similar experience as Lot, we’re now able to get a much clearer idea of what basanizo really means, and in turn, what the torment in spoken of in Revelation chapter 9 really means.
God refers to Lot’s “righteous soul” because each elect child of God receives a new born again soul at the moment of salvation. And the nature of the new soul is that of sinless perfection:
1 John 3:9 Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God.
Once truly saved, an individual immediately possesses a righteous soul that cannot sin for the very reason that it is born of God. Of course, the newly born again person remains in their physical body and the body can and does still sin. Which is why 1 John 1:8 says anyone who says they are without sin is a liar. God’s elect still sin, only the sin is located in their members and no longer in their soul.
Holy God indwells the elect in their soul which is one reason why it must be sinless. The Holy One could not possibly indwell a heart (soul) that was still sinful in any way as He cannot dwell with sin.
After experiencing this glorious grace of God in salvation, the elect child of God whose soul has been made righteous goes out into the wicked world and encounters evil after evil as he has always done before. But now, the evil words he hears spoken trouble his new soul. The evil things he sees happen also grieve his new soul. The evil acts and deeds that occur all around him on a daily basis vex his soul. Oh, how troubling it is for the holy and sinless soul within God’s elect to hear, see, and experience all the foul thoughts, words, and deeds of man while living in this world. It is torment for them. And, over the course of the 23 years great tribulation period wherein Satan was loosed and sin multiplied in the churches and across the face of the earth, the righteous soul of God’s elect was especially vexed (tormented).
But now, though, the Bible reveals the tables have turned. The object of the wrath of God is now the world itself. The oppressor (the tormentor) is now the one oppressed (tormented).
Revelation 18:5 For her sins have reached unto heaven, and God hath remembered her iniquities.
6 Reward her even as she rewarded you, and double unto her double according to her works: in the cup which she hath filled fill to her double.