This is an important matter for those in Christ to understand, because it's about recognizing the true enemies of Christ that work here on earth. To not know and recognize them is to make it possible for them to deceive you, because just like the devil knows Scripture as shown in Luke 4 when he quoted a passage to our Lord with adding one small phrase to it, that's how deceptive these workers of iniquity are. I've yet to find a Christian online forum where they weren't present either.
It began with Cain murdering Abel and being cast to the land of Nod. See Gen.4 for the type of mentality. See about the gainsaying of Core per Jude, and about certain men that were ordained to work this condemnation of being against God and His Son.
In ancient Sumer (area of Babylon before it became Babylon), one of Semitic birth came to the Sumerians per their written history, and gave them knowledge of canal building, i.e., sciences, and he became their king. His name was Sargon I. He also began the first pagan dragon devil worship known in written history which became the Baal worship written of in God's Word which then trickled to other nations like ancient Egypt, Greece, far east, etc.
God gave the pagan Canaanites 430 years to repent according to when He spoke to Abraham, saying the iniquity of the Amorites was not yet then full (Gen.14). When He led the children of Israel out of captivity from Egypt, that's when He pronounced His judgment upon the nations of Canaan for the iniquities they were doing. Israel failed to destroy all the Canaanite nations which God told them to, so He said He would use those workers of iniquity to test Israel with, to see if His people would follow Him or not, that He would not drive those leftover Canaanites out from among them (Judges 2 & 3). Lot of those Canaanite leftovers became bondservants to Israel (Judges 9; 1 Kings 9).
Israel always had a problem with them, even making the mistake of marrying with them (Ezra 9). Per 1 Chronicles 2:55, the Kenites of the nation of Canaan mostly became Israel's scribes in charge of keeping God's Holy Writ, making copies, and keeping them in order, etc.
God told His people to not marry with them, because they would turn Israel's heart away from Him by their pagan influences and idols, which is exactly what happened in Solomon's day which is why God rent the kingdom of Israel in his days. This matter is still... in effect for today, believe it or not, and it will continue all the way up to Christ's return. It's about the hidden tares of the field in Jesus' parable of Matt.13. The problem is we cannot truly know who all these workers are, we can only know them by their works, judging their fruit like our Lord Jesus said.
One of the biggest proofs of their continued existence and influence is with the secret societies of fraternities of initiation into the "Mysteries" of occult paganism. These fraternities meet in secret, hold pagan style rites in secret recognizing the pagan religions of history and many things of the ancient arcana from ancient Egypt, Greece, Rome, etc. (see British Mason John Robison's work Proofs Of A Conspiracy written in 1798 for details of some of those initiations and rites and working against God's people).
This is why our Lord Jesus rebuked the scribes and Pharisees at His first coming (see John 8, as He compared them to the way of Cain, and being followers of the devil). The scribes (Kenites of Canaan) and many of the Pharisees (not all) were full of the old Canaanite bondservants that migrated in with Israel which eventually worked their way up into the priesthood (see Book of Ezra about the Nethinims and priests).
I know in most Churches this is never taught, because we want to think that the hearing of The Gospel can turn even the darkest soul to believe on Christ Jesus and become a member of His Body. It's true that His Salvation is open to them also IF they will hear and believe and follow Him. But the Jude 1:4 Scripture shows us that God has ordained these certain ones to be against Christ for this present world, and that won't change for this world:
Jude 4
4 For there are certain men crept in unawares, who were before of old ordained to this condemnation, ungodly men, turning the grace of our God into lasciviousness, and denying the only Lord God, and our Lord Jesus Christ.
KJV