They are reading the same Bible, yet they believe different things......
So how is one to know which one is correct?.
If one is correct, the religion is of Christ and if it is of Christ then it is of God.
On the other hand if a religion isn't then that belongs to another person, man-made and not of God.
The Bible tells us how an incorrect [false] preacher/religion will behave
How they will act and how they conduct themselves.
In the first century Church of Christ, false teachers came from within the church.
Acts 20:29 New Living Translation (NLT)
I know that
false teachers, like vicious wolves, will come in among you after I leave, not sparing the flock.
And this false teachers was aided by the might of the Roman Empire to achieve their apostasy. Which some of them are recorded in the annals of history.
Diocletianic Persecution - Wikipedia
Fast forward to the present time, the Bible describes them as:
2 Peter 2:1-3 New Living Translation (NLT)
But there were also false prophets in Israel, just as there will be false teachers among you. They will cleverly teach destructive heresies and even deny the Master who bought them. In this way, they will bring sudden destruction on themselves. Many will follow their evil teaching and shameful immorality.
And because of these teachers, the way of truth will be slandered. In their greed they will make up clever lies to get hold of your money. But God condemned them long ago, and their destruction will not be delayed.
Galatians 4:17 New Living Translation (NLT)
Those false teachers are so eager to win your favor,
but their intentions are not good. They are trying to shut you off from me so that you will pay attention only to them.
So instead of teaching the pure doctrines of the Bible, they will divert your attention to their own stories, their own personal experiences and create the illusion that you be rich beyond your wildest dreams if you show them your money - that is prosperity gospel.
1 Timothy 4:1-3 Douay-Rheims 1899 American Edition (DRA)
Now the Spirit manifestly saith, that
in the last times some shall depart from the faith,
giving heed to spirits of error, and doctrines of devils,
Speaking lies in hypocrisy, and having their conscience seared,
Forbidding to marry, to abstain from meats, which God hath created to be received with thanksgiving by the faithful, and by them that have known the truth.
When you see these things [as the Bible records it] - well you can be sure they are not going "upstairs".
All Christians I have seen believe they are truly His, yet they have nothing to base this upon except their feelings.
I mean they have no proof that their understanding of the scriptures is any better than anyone else's.
Not all Christians are truly His
And this fact was mentioned by Jesus Christ himself
Matthew 7:21-23 New Living Translation (NLT)
“
Not everyone who calls out to me, ‘Lord! Lord!’ will enter the Kingdom of Heaven. Only those who actually do the will of my Father in heaven will enter.
On judgment day many will say to me, ‘Lord! Lord! We prophesied in your name and cast out demons in your name and performed many miracles in your name.’ But I will reply, ‘I never knew you. Get away from me, you who break God’s laws.’
These are "Christians" who performed many things in Jesus name.
They have cast out demons, removed unclean spirits on those who were possessed
They have performed great things in Jesus name and even preached the Bible in his name.
These people are considered much nearer to heaven in an ordinary "Christian's" eyes
One may say, they are heaven bound because it seems like Jesus is answering their prayers as they asked for these miracles to be done in Jesus holy name.
But on Judgement Day what will Jesus tell them?
Sad isn't it? From Day 1, Jesus never knew this "Christian"
Because in fact they were really not really Christian even if they feel very Christian
So these people are MANY as the Bible says, will not going "upstairs"