HOW or WHEN does having false beliefs make one a false Christian?

';Jesus said to him, “If I will that he remain till I come, what is that to you? You follow Me.”


Then this saying went out among the brethren that this disciple would not die. Yet Jesus did not say to him that he would not die, but, “If I will that he remain till I come, what is that to you?”'; (John 21:22, 23 NKJV)





Were the disciples who misunderstood Jesus' words, concluding that John would not die, false Christians?HOW or WHEN does having false beliefs make one a false Christian?
The wrong conclusion that those believers jumped to was not an article of faith that determines whether a person is a Christian or not. There is only one article of faith that makes a person a Christian - that only faith in what Jesus accomplished at Calvary will save anyone from their sins. Anybody who trusts in anything other than faith in Christ for their salvation remains unsaved. Nobody can come to God with anything in their hand, to offer as a contribution towards forgiveness and salvation. ';Just as I am, without one plea, but that your blood was shed for me'; goes the old hymn.





A person could claim to believe a whole raft of biblical doctrines yet still not be a Christian! You see, Christianity is not a head-trip. It's a heart transplant, and only humble, total faith, will bring about the miracle of a heart that beats for God. Once God brings a spiritually dead person to spiritual life (the new birth Jesus spoke of in John chapter 3), then they have become a Christian. Thereafter, they grow in knowledge and understanding. It cannot work the other way around!





The disciples who misunderstood Jesus' words did so because they had wrong expectations for how the Kingdom of God would be manifested. Throughout the centuries, many Christians have fallen into the same trap, yet that did not cast them out of the Kingdom! They were going beyond the things written; they were not minding their Christian business (because they were making judgments and pontificating on inappropriate matters). They had, however, put all their faith in Christ to be saved, and that cannot be done by a false Christian. Actually, there is no such thing as a false Christian. Once a person becomes a Christian, they are a Christian, pure and simple. The world is full of pseudo-Christians, however; those who claim to be Christians but who have not yet been born again of the Holy Spirit. Christians can be mistaken about many things, but if they have been born again of the Holy Spirit, they remain Christians, their mistakes being sorted out as they grow in grace. It's believing you don't have to be born again that is the hallmark of false Christianity.HOW or WHEN does having false beliefs make one a false Christian?
It's one thing to misunderstand issues that have no bearing on salvation.





It's another thing to not believe the right things for salvation.





If a person rejects the truth that Jesus is God, and/or rejects the Trinity, or if the person adds works to faith alone in Jesus for salvation, then the person is unsaved.





They don't have to be unsaved. The truth about Jesus is that the only way to be saved and to get into heaven and avoid being sent to eternal hell, is by believing in faith alone that Jesus, who is God, died on the cross for our sins as FULL PAYMENT for all our sins, and then Jesus rose from the dead (1 Corinthians 15:1-4). Believe in Jesus alone for salvation, and you will be in heaven, no matter what! Salvation is a FREE GIFT that happens in a split second when you believe in Jesus alone to save you! It is impossible to lose or ';leave'; salvation (John 6:39-40, John 10:28, 1 John 5:13).
';False belief'; is an oxymoron.





The attributes of TRUTH and FALLACY can only be assigned to facts and logical conclusions.





BELIEF/FAITH is a matter of personal insight or leanings.


As such, it has nothing to do with facts or logical conclusions.
John 17:3 makes it quite clear


3 Now this is eternal life: that they may know you, the only true God, and Jesus Christ, whom you have sent





If you don't know the truth it would appear eternal life is not what you will get.
when one is not born again..