At the risk of sounding like an anarchist...

[JohnD]

Matthew 7:21–23 (AV)
21 Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
22 Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works?
23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity.

There are no words to describe this tragedy; to find out only then (when it is too late to do anything about it) that you believed the wrong belief, or refused to believe at all and death is real, Jesus is real, and hell is real. And you are going there.

My takeaway from this is twofold:

1.    become absolutely certain that you not only believe Jesus Christ, but that you believe in the genuine Jesus Christ
2.    that you take no one else's word for it than God's

There is no other way to be that certain.

If we went by what most people subscribe to, getting into heaven is a group plan. "I'm a Baptist." "I'm a Catholic." ...and so on.  
Without even realizing it in most cases, the people who buy into this have taken the word of other human beings about their eternal destination. A most dangerous thing!

People do more research into buying a home or a car or which school to attend. How tragic to end up as one of the individuals Jesus refers to above because their only research is to find which group of people they agree with the most. This is banking on the group and the individual correct in their theology.

But what if they are not?

Proverbs 14:12 (AV)
12 There is a way which seemeth right unto a man, but the end thereof are the ways of death.

Proverbs 16:25 (AV)
25 There is a way that seemeth right unto a man, but the end thereof are the ways of death.  

1 Thessalonians 5:21 (AV)
21 Prove all things; hold fast that which is good.  

1 John 4:1 (AV)
1 Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.

How do we test / prove the spirits and all things? By our wits? Proverbs 14:12 By our scholars? Proverbs 16:25...

By our traditions?
Mark 7:13 (AV)
13 Making the word of God of none effect through your tradition, which ye have delivered: and many such like things do ye.

The NIV says "you nullify the word of God by your traditions..."

What drew the greatest human opposition  to Jesus Christ during his walk on Earth? The traditions of man.

1 Corinthians 15:1–4 (AV)
1 Moreover, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand;
2 By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain.
3 For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures;
4 And that he was buried, and that he rose again the third day according to the scriptures:

According to the scriptures...

The only scriptures in existence at the time of Paul's writing in 1 Corinthians was the Old Testament / Tanakh. And by Jesus' day, the Sanhedrin (Jewish leadership consisting of priests, Pharisees, Sadducees, and Scribes / Lawyers) had already nullified the word of God to the point that they did not / would not recognize Jesus as the promised Messiah. They had written proof (prophetic scriptures which he fulfilled to the letter) and his miracles and teaching to go by...

Fast forward to today.

If we lived in those days, we believe, we would not make the same errors the Sanhedrin made... or Peter... or David... or Moses... or Noah... I just have to chuckle at how good we are at deceiving ourselves especially over how "good" we are.

In fact, we do the same things the Sanhedrin did. We buy into the traditions of man as the authority over scripture. We deceive ourselves and others to the contrary. But we do this almost abjectly.

A woman pastor I once encountered bristled at my question "From where do you get authority to be a pastor?" She was ready to argue the cultural shame tactic for treating women as second class citizens etc. I assured her I was not out to clobber her with 1 Timothy 2:9-15 (the typical anti-female pastorate text). So she confidently named the denomination she belonged to.

"Hmph." I said. "I get my authority as a priest of God straight from Jesus Christ himself."

The glimmer of camaraderie dissolved into a look of 'get me away from this nut.' And she began making excuses for having to leave. I assured her I could back my claim up with scripture... which disarmed her slightly.
Footnote: the fact that humanists and traditionalists are deceived into believing that the Bible is their ultimate authority means they will not run from it until you point out where the word of God repudiates their traditionalist / humanist belief system. Many were the Jehovah's Witnesses or Mormons who darkened my doorstep who ended up fleeing for their cultic theology because I showed them where God's word proves them false.

The Church is no different.

There are no sacred cows. Meaning no one and no thing is above the scrutiny of proof by the word of God (making it the ultimate authority).

I showed her:

Revelation 1:6 (AV)
6 And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen.

Revelation 5:10 (AV)
10 And hast made us unto our God kings and priests: and we shall reign on the earth.

1 Peter 2:3–9 (AV)
3 If so be ye have tasted that the Lord is gracious.
4 To whom coming, as unto a living stone, disallowed indeed of men, but chosen of God, and precious,
5 Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ.
6 Wherefore also it is contained in the scripture, Behold, I lay in Sion a chief corner stone, elect, precious: and he that believeth on him shall not be confounded.
7 Unto you therefore which believe he is precious: but unto them which be disobedient, the stone which the builders disallowed, the same is made the head of the corner,
8 And a stone of stumbling, and a rock of offence, even to them which stumble at the word, being disobedient: whereunto also they were appointed.
9 But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light:  

"Oh, well, yes of course, in a general sense," she mused.

But I held her feet to the fire. "Hold on a minute. You were asked by whose authority you are a pastor, and you responded by man's authority / your denomination. I showed you where I get mine from the scripture that states it comes from Christ himself. It also states that we all are priests of God who believe in Jesus Christ which settles the women preacher debate once and for all."

Her demeanor changed to resentment. "Well we all interpret the Bible differently." She said.
"Ah! The very point I was driving at. The traditions of man that nullify the word of God are based on the different interpretations of the Bible.... because man has no business interpreting the Bible."

Resentment and anger filed her eyes.

"Now hold on, I can prove it with the Bible."

"Your interpretation of the Bible..." she said scowling.

I opened my NKJV Bible to this passage and asked her to read it.

2 Peter 1:20–21 (NKJV)
20 knowing this first, that no prophecy of Scripture is of any private interpretation,
21 for prophecy never came by the will of man, but holy men of God spoke as they were moved by the Holy Spirit.

Her shoulders sank as she got to the last part of the text. Most do not get the enormity of the deception in the world about scripture... not even when confronted by this passage. But she seemed to. I do not know if it "took" because I've not seen or heard from her again.

But there it is... the Bible is prophetically written by the Holy Spirit and it is to be interpreted only by the Holy Spirit (which we authenticate it's actually him by 1 Thessalonians 5:21 and 1 John 4:1).

How? How do we authenticate it is the actual, genuine Holy Spirit doing the interpretation of scripture?

Acts 17:11 (NKJV)
11 These were more fair-minded than those in Thessalonica, in that they received the word with all readiness, and searched the Scriptures daily to find out whether these things were so.

2 Timothy 3:16–17 (NKJV)
16 All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness,
17 that the man of God may be complete, thoroughly equipped for every good work.

We enter life individually. We live life individually. We die individually. We face judgment individually. Heaven or hell depends entirely upon whether we individually believe in the Lord Jesus Christ or not.

It's up to us individually to make absolutely sure. For there are false Christs in the world... Jesus himself warned of them:

Matthew 24 (NKJV)
4 And Jesus answered and said to them: “Take heed that no one deceives you.
5 For many will come in My name, saying, ‘I am the Christ,’ and will deceive many.
9 “Then they will deliver you up to tribulation and kill you, and you will be hated by all nations for My name’s sake.

11 Then many false prophets will rise up and deceive many.

15 “Therefore when you see the ‘abomination of desolation,’ spoken of by Daniel the prophet, standing in the holy place” (whoever reads, let him understand),

21 For then there will be great tribulation, such as has not been since the beginning of the world until this time, no, nor ever shall be.
22 And unless those days were shortened, no flesh would be saved; but for the elect’s sake those days will be shortened.
 
23 “Then if anyone says to you, ‘Look, here is the Christ!’ or ‘There!’ do not believe it.

24 For false christs and false prophets will rise and show great signs and wonders to deceive, if possible, even the elect.

25 See, I have told you beforehand.

26 “Therefore if they say to you, ‘Look, He is in the desert!’ do not go out; or ‘Look, He is in the inner rooms!’ do not believe it.

27 For as the lightning comes from the east and flashes to the west, so also will the coming of the Son of Man be.

37 But as the days of Noah were, so also will the coming of the Son of Man be.
38 For as in the days before the flood, they were eating and drinking, marrying and giving in marriage, until the day that Noah entered the ark,
39 and did not know until the flood came and took them all away, so also will the coming of the Son of Man be.

42 Watch therefore, for you do not know what hour your Lord is coming.
43 But know this, that if the master of the house had known what hour the thief would come, he would have watched and not allowed his house to be broken into.
44 Therefore you also be ready, for the Son of Man is coming at an hour you do not expect.
45 “Who then is a faithful and wise servant, whom his master made ruler over his household, to give them food in due season?
46 Blessed is that servant whom his master, when he comes, will find so doing.
47 Assuredly, I say to you that he will make him ruler over all his goods.
48 But if that evil servant says in his heart, ‘My master is delaying his coming,’
49 and begins to beat his fellow servants, and to eat and drink with the drunkards,
50 the master of that servant will come on a day when he is not looking for him and at an hour that he is not aware of,
51 and will cut him in two and appoint him his portion with the hypocrites. There shall be weeping and gnashing of teeth.

There are numbers of false Christs, fake Jesus' and some are very Christ-like.  

2 Corinthians 11:3–4 (NKJV)
3 But I fear, lest somehow, as the serpent deceived Eve by his craftiness, so your minds may be corrupted from the simplicity that is in Christ.
4 For if he who comes preaches another Jesus whom we have not preached, or if you receive a different spirit which you have not received, or a different gospel which you have not accepted—you may well put up with it!

This is a good proof text to contrast the cults outright denial of the Godhead (substituting a contrived belief system that redefines God). But what about within the ranks of so-called Orthodox Christianity?

Depending on which Pope is in office, Roman Catholics believe Mary the mother of Jesus is the co-redemptrix with Christ. Baptists believe you have to be water baptized to be saved. In fact all Christian denominations in some fashion or other teach a works faith (to be saved or to remain saved) based on their tradition of bringing elements of the Old Testament into the New.

How many of the differing denominations teach that the Holy Spirit is the authority and the only one to interpret the Bible?
Which denomination teaches that all believers are priests of God rather than the Old Testament division of clergy and laity?

Why is it that despite the prayers of the Lord Jesus Christ in John 17 for the Church to be one "as we are one" (he and the Father)... there are hundreds of denominations and thousands of factions within them?

At this point most consider that cultists like Joseph Smith Jr. or Charles Taze Russell made these kinds of arguments and led their followers into hell. This is not because challenging the condition of the Church is wrong, it is because they simply substituted their human traditions for the ones they exposed in the Church. Follow not this author! Follow Christ!

Become an individual believer in Christ (one-to-one), and first thing (just like the Bible says) know and proceed from the understanding that the Holy Spirit is the Author and Interpreter of the Bible. If you don't get this first step right... it matters not how high you climb on the spiritual ladder of Bible knowledge... it will be in error.