Even him, whose coming is after the working of Satan with all power and signs and lying wonders,And with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved.And for this cause God shall send them strong delusion, that they should believe a lie: 2Th 2:9
I think the key is found in the word wonders as to the source.
The strong delusion to believe the lie would be in respect to those who add to the scriptures coming from another source of faith other than... as it is written called a “lying wonder”. With wonder the faith principle meaning the unseen, made know by what it seen, a sign.
In that way a clear distinction between a sign and lying wonder must be made.Its an evil generation the generation of Adam that does seek after signs used as wonders in order to bring belief, faith
The focus is on the wonder that which bring faith and not so much the sign. Signs are for observing while wonders draw to the unseen.
Today seeing what we had in part up until the last book was written giving us the perfect as in compete. It would be any one who says they have received a vision or a new revelation. That would make them a liar. The possibility of God bring any new revelation is sealed up till the end .
Then if any man shall say unto you, Lo, here is Christ, or there; believe it not.For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, "if it were possible", they shall deceive the very elect. Mat 24:23
In the context of 2 Thessalonians 2nd chapter, signs and lying wonders that opposes the tradition taught of us as Paul reminded us in verses 13-15 has to do with those that preach receiving the Holy Spirit apart from salvation after a sign of tongues ( which never comes with interpretation & can be found in the world's religions, idolatry, occult, as well as cults in christianity ) . That is the whole point for Paul reminding us how and when we had received the Holy Spirit in vs 13-15.
So like all those movements of the "Spirit" where they believe the Holy Spirit is coming and falling on saved believers again and again and again is NOT the Holy Spirit.
Even they that preach receiving the Holy Spirit apart from salvation after a sign of tongues is not of Him.
Or they that preach receiving ANOTHER baptism with the Holy Spirit with the evidence of tongues.
And yet God's gift of tongues was never to serve as a sign or proof or evidence to the already saved believers for anything. 1 Corinthians 14:22
And so saved believers preaching this apostasy of receiving tongues ( which is why it NEVER comes with interpretation ) by seeking to receive what they believe is the Holy Spirit apart from salvation, have fallen away from the faith in giving heed to seducing spirits and doctrines of devils, having their conscience seared with a hot iron in hypocrisy by calling for the Holy Spirit to come when He has been in them since their salvation and CANNOT be received again.
That is the strong delusion that God will permit for believing the lie ; that iniquity that a saved believer can receive the Holy Spirit apart from salvation after a sign of tongues with no interpretation or/and any other sensational signs of confusion in the flesh.
So the falling away from the faith is happening now and in droves, indicating that God will be coming soon at the pre trib rapture event to judge His House first....
May God peradventure to recover some from this snare of the devil to chase no more after seducing spirits to receive after a sign by returning to their first love, the Bridegroom, and be free from being a captive of the devil to shun vain & profane babbling to pray normally which is the will of God the Father in Christ Jesus concerning any saint.
Otherwise, they are at risk of being cast into the great tribulation at the pre trib rapture event to be received later on as vessels unto dishonor in His House after the great tribulation.