How do we identify false teachers?

The Bible clearly talks about the "fruit of the Spirit" (Gal 5:22). It is the outcome of peoples beliefs that mark them for what they are.

Do the outcomes of their beliefs result in the kind of things we see Jesus doing and that we see throughout the New Testament? (John 14:12, Acts 2:17)

My own experience is that those who are true to their Father carry the power and authority of Heaven (as befits those who are adopted by the Father into His kingdom). It makes them interesting and often uncomfortable people to be around! (It's not just in Acts you can see this stuff happening but throughout the world today)

Unfortunately, it is not only easy to hide wrongdoing but also easy to step off the right path as happened to a church that I used to go to. So it is important for all of us who consider ourselves "citizens of Heaven" to keep watch over the Church and those who claim the authority of God and to hold them accountable. Just as they should hold us accountable for our actions.

As an aside, I believe that we should be doing this as Earthly citizens too - something which would go a long way towards fixing some of the ills of our democratic governments.

EDIT: Jas, sorry I clearly didn't explain everything I needed to. I am absolutely in agreement with you about the dangers. I also totally agree with you regarding the importance of 1 Cor 13, thanks for highlighting that. You are right that, without the evidence of God's infinite love, everything else is not only pointless but extremely dangerous. In fact, that is the point I was trying to make - sadly I didn't manage to.

To expand then, the outcomes that I am talking about include the demonstration of and the act of God's love. A Christian who demonstrates the "Gifts of the Spirit" as often recognised (tongues, healing, etc.) without also demonstrating the Love and discernment that also characterises God's interactions with us clearly has something wrong. This was evident in one of the big US churches recently where they were seeing many signs and wonders but were drifting away from the love and intimacy - they ended up with some of the church leaders getting into trouble. I also made reference to this in my fourth paragraph, another case where a strong, dynamic church went horribly wrong.

None-the-less, this does not excuse us from taking hold of the responsibilities that come with being a prince of the ultimate kingdom. God, through Jesus and the Holy Spirit, has given us a lot of power and authority. It is not just church leaders who have been given this power, we all have. And so we all have the tools already - to discern right from wrong - to discern good from bad. To make sure we keep these things in perspective, we submit ourselves to the examination and accountability of our fellow Christians as they did in the early church. We also choose to study God's Word to see if what we are thinking and doing matches what He has passed to us through that medium.

"Beloved, do not believe every spirit, but test the spirits to see whether they are of God; for many false prophets have gone out into the world. By this you know the Spirit of God: every spirit which confesses that Jesus Christ has come in the flesh is of God, and every spirit which does not confess Jesus is not of God. This is the spirit of antichrist, of which you heard that it was coming, and now it is in the world already. Little children, you are of God, and have overcome them; for he who is in you is greater than he who is in the world. They are of the world, therefore what they say is of the world, and the world listens to them. We are of God. Whoever knows God listens to us, and he who is not of God does not listen to us. By this we know the spirit of truth and the spirit of error." (1 John 4:1-6)

That's the biblical answer.

The obvious followup question would be - who are the "us" today in the "listens to us" part? The "us" in those times were obviously the apostles. But what about today? That's where things get interesting. For me, I believe it's the Magisterium, the college of bishops in union with the pope who are now holding the same "episcopal offices" (Greek, episkope. See Acts 1:20 and 1 Tim 3:1) - that the apostles held at that time.

1 John is really the 'discernment' Epistle showing many ways that false teachers can be identified. The main thing is to look at the life and doctrine of a teacher to ensure they stick to the basic Christ centred ideas and life of love. The basic rules are:

False teachers do not love Christians and they live in wickedness. Real Christians know how sinful they are, confess their daily sins, but do not love the world. Real Christians love God, as proven in their love of those who believe in Christ for the forgiveness of their sins, that is God's children.

If we claim we have not sinned, we make him out to be a liar and his word is not in us. (1 John 1:10)

The Lord's daily prayer included 'forgive us our sins' (Math 6:12). Every Christian knows that they sin every day because nobody loves God with all the heart, soul and mind, which is the greatest command. (Math 22:37)

Whoever says, “I know him,” but does not do what he commands is a liar, and the truth is not in that person. (1 John 2:4)

Some may seem correct in doctrine, but live in open sin. For example they may say it is alright to commit adultery, practice h*m*sexuality, or the worship of someone other than God, which is idolatry, etc. Such a person is like the Devil appearing as an angel in word, but betrayed in action.

Anyone who claims to be in the light but hates a brother or sister is still in the darkness. (1 John 2:9)

A Christian cannot hate another person in the intense way that this implies. It is impossible for a born again; regenerate should to be filled with hate because God’s Spirit remains in them. This especially holds true for our attitudes towards any who belie in Christ for the forgiveness of their sins. This is the ‘brother or sister’ being mentioned. Therefore churches and cults, that consider their denomination as the only group that will be saved, are built upon false teachers. Paul says; let such teachers be ‘accursed’ even if they were a Pope, Saint, Apostle, or even an Angel. (Gal 1:8) Anyone who genuinely believes in Christ, proven by their love of all the others who also believe, will have eternal life. (John 3:16, 1 John 5:11-13)

Do not love the world or anything in the world. If anyone loves the world, love for the Father is not in them. (1 John 2:15)

Anyone who puts money, sex, career, worldly status, or religious status before the gospel loves the world and is not a Christian. (1 John 2:16)

Whoever does not love does not know God, because God is love. (1 John 4:8)

This cuts to the spirit of all true Christians. The Holy Spirit is a loving Spirit so if that Spirit is within a soul, that soul will love others. When somebody loves us we can tell. Not only does this help us discern our own attitudes but if somebody seems right in doctrine but is always angry, impatient, not kind, jealous of others, bragging all the time, always argumentative, selfish, or any other non-loving characteristic, the Bible seems to say we should switch channels and listen to someone else. They are clanging gongs (1 Cor Ch 13)

False teachers deny the incarnation of Christ in one way or another. They either deny the Father, Son, or Holy Ghost, or they deny the incarnation, or atoning sacrifice of sin on the cross. They might deny the whole gospel by thinking their good works will save them rather than Christ. Real Christians believe that God assumed human nature in Christ, and that by faith in Christ alone we have eternal life.

Who is the liar? It is whoever denies that Jesus is the Christ. Such a person is the antichrist—denying the Father and the Son. (1 John 2:22)

This is how you can recognize the Spirit of God: Every spirit that acknowledges that Jesus Christ has come in the flesh is from God. (1 John 4:2)

The gospel hinges on believing that the eternal Son of God took on human nature to offer his soul and body for the punishment of your sin, and my sin. In fact faith is this one statement determines who Christians are and who liars are.

And this is the testimony: God has given us eternal life, and this life is in his Son. Whoever has the Son has life; whoever does not have the Son of God does not have life. I write these things to you who believe in the name of the Son of God so that you may know that you have eternal life. (1 John 5:11–13)

A Christian can be sure they have eternal life by relying on the death of Christ for their forgiveness. If they rely on their own works by being a good moral person, or being baptised into a specific church, they may still yet go to hell.

In the end, discernment is easy for those who have the Holy Spirit. Jesus said:

By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles? (Matt 7:16)

The Bible lists the fruit of the Spirit as love, joy, peace, etc. (Gal 5:22) The nature of fruit corresponds to the type of tree from which it grows, and all Christian have been engrafted into Christ as the root, who’s life is our sap and nutrient. Naturally this fruit is not just the attitude but also the doctrine of justification in Christ by faith apart from the works of the law, as is the argument of the entire Bible.