As the scripture says, He didn't "know them" because they continued to commit sin.
Incorrect. He didn't know them at all, period. They were workers of lawlessness, but that not why Jesus didn't know them.
The point is, as Jesus didn't know them they didn't do any of the supernatural works by the Spirit of Christ.
There is "another spirit" that can do powerful works and make it seem like its in Christ's name:
For if he who comes preaches
another Jesus whom we have not preached, or if you receive
a different spirit which you have not received, or
a different gospel which you have not accepted-- you may well put up with it! (2 Cor. 11:4 NKJ)
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1 Now concerning spiritual gifts, brethren, I do not want you to be ignorant:
2
You know that you were Gentiles, carried away to these dumb idols, however you were led.
3 Therefore I make known to you that no one speaking by the Spirit of God calls Jesus accursed, and no one can say that Jesus is Lord except by the Holy Spirit. (1 Cor. 12:1-3 NKJ)
Paul warned the Corinthians, who once were
Experiencers led by evil spirits---(ὡς ἂν ἤγεσθε, ἀπαγόμενοι) "however ye were led".
The Greek implies they were led like animals to the slaughter, anywhere the spirits wanted, even unto thinking dumb idols could hear prayer and speak!
That means their ability to think critically, evaluate facts and arrive at common sense solutions, was completely subverted. They followed their experiences, demon inspired experiences.
Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils; (1 Tim. 4:1 KJV)
Paul warns:
"Don't be fooled again by spiritism"----by those claiming to speak by the Spirit of Christ. Test them while under the influence of "the Spirit", if they say "Jesus is accursed" that is NOT the Holy Spirit speaking:
1 Now concerning spiritual gifts, brethren,
I do not want you to be ignorant:
2 You know that you were Gentiles, carried away to these dumb idols, however you were led.
3
Therefore I make known to you that no one speaking by the Spirit of God calls Jesus accursed, and no one can say that Jesus is Lord except by the Holy Spirit. (1 Cor. 12:1-3 NKJ)
We are commanded to test the spirits (1 John 4:1)
Lest Satan should get an advantage of us: for we are not ignorant of his devices. (2 Cor. 2:11 KJV)