The writing we call 1 John is written by the Apostle John to deal with a specific situation occurring in the churches he oversaw in Asia Minor. False teachers had caused his flock to doubt that they possessed eternal life (1 John 5:13).
1. The false teachers (or prophets) were part of the Johannine Community. They have left the church, or perhaps were forced out. They likely were in leadership positions based on their influence and the fact that they are teachers (1 John 2:18-19; 2 John 1:7-11; 4:1).
2. They relied on Scripture to make their arguments and thought of themselves as having the correct interpretation and path to “getting saved” (Polycarp Letter to Philippians chapter 7; Irenaeus Ad Haer 3.11.7).
So firm is the ground upon which these Gospels rest, that the very heretics themselves bear witness to them, and, starting from these [documents], each one of them endeavours to establish his own peculiar doctrine. (Irenaeus Ad Haer 3.11.7)
3. They denied that Jesus was the Christ who had come in the flesh. They held that Jesus was just a man who was spiritually indwelt with the Christ. The Christ was a guide who taught through Jesus and left him at the cross. Therefore Jesus did not die to deal with sin (1 John 2:22-23; 4:2-3; 2 John 1:7; Ignatius Letter to Smyrna chapter 2, 5, 6; Trallians chapter 10; Polycarp Letter to Philippians chapter 7; Irenaeus Ad Haer 3.11.3).
Now, He suffered all these things for our sakes, that we might be saved. And He suffered truly, even as also He truly raised up Himself, not, as certain unbelievers maintain, that He only seemed to suffer, as they themselves only seem to be [Christians]. … Let no man deceive himself. … if they believe not in the blood of Christ, shall, in consequence, incur condemnation. (Ignatius, Smyrna chapter 2, 6)
For whosoever does not confess that Jesus Christ has come in the flesh, is antichrist; and whosoever does not confess the testimony of the cross, is of the devil; and whosoever perverts the oracles of the Lord to his own lusts, and says that there is neither a resurrection nor a judgment, he is the first-born of Satan. (Polycarp Letter to Philippians chapter 7)
4. They had a low view of sin. They taught that you could live however you wanted without affecting your salvation as long as you had the correct knowledge and were pursuing spiritual enlightenment since the body was worthless and evil. The false teachers did not require a Savior to deal with sins since they claimed they had no sin (1 John 1:6,8-10; 3:3,8-10; Irenaues Ad Haer 1.13.6).
They assert that they themselves know more than all others, and that they alone have imbibed the greatness of the knowledge of that power which is unspeakable. They also maintain that they have attained to a height above all power, and that therefore they are free in every respect to act as they please, having no one to fear in anything. (Irenaues Ad Haer 1.13.6)
They lead lives of unrestrained indulgence. The character of these men is very plainly pointed out in the Apocalypse of John, [when they are represented] as teaching that it is a matter of indifference to practise adultery, and to eat things sacrificed to idols. (Irenaues Ad Haer 1.26.3)
5. John did not view these false teachers as “carnal” or “back-slidden” people who possessed eternal life. He saw them as unsaved people who were deceivers, antichrists, devils, and friends of the world (1 John 2:26; 2:18-19; 3:7-10; 4:5; 2 John 1:7) who claimed to have fellowship with the Father and Son but did not and thus do not possess eternal life (1 John 1:6; 5:10-12; 2 John 1:9). If Irenaeus’ testimony is correct these false teachers are related to the Nicolaitans who deeds Jesus hated (Irenaeus Ad Haer 1.26.3; 3.11.1; Rev 2:6,14-15).
John, the disciple of the Lord, preaches this faith, and seeks, by the proclamation of the Gospel, to remove that error which by Cerinthus had been disseminated among men, and a long time previously by those termed Nicolaitans, who are an offset of that “knowledge” falsely so called, that he might confound them, and persuade them that there is but one God, who made all things by His Word;…
These observations are based on 1 John, 2 John, Revelation, and extant writings from Ignatius, Polycarp, and Irenaeus.
I would like to thank Derek Knight my co-teacher who helped research the background on these false teachers