Hi Gino,

Thanks for the nice reply.  You asked:

I was wondering, what do you personally think about that whole subject that you referred to?

I think Once Saved Always Saved is not what the Bible teaches.  Here is an article I wrote on the subject a couple of years ago.  http://jesusisthewaythetruththelife.com/node/195

How does a person get saved, and how do they get to heaven?

A person gets saved when they believe on the Lord Jesus, recognizing that he died for their sins, rose from the dead on the third day.  

The confusion is coming in with the word 'believe' in there.  The Greek present tense verb indicates an action happening in the present and continuing.  So you could say that we need to believe and keep on believing.  If you believe Jesus, it follows that you will abide in Him, follow Him, obey Him.  He said He was Lord, and you believe that, no?  That means He is in charge.   Keep following Him.  If you stumble, repent, stop what you were doing that was sin, and get up and keep going.  Admit it and quit it.  

The Holy Spirit works on us as we walk through the Christian life, cleaning us up, teaching us.  But we are warned not to quench the work of the Spirit.  We should be submitting to this work of the Spirit.  

James 4:7-10 King James Version
7 Submit yourselves therefore to God. Resist the devil, and he will flee from you.
8 Draw nigh to God, and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye double minded.
9 Be afflicted, and mourn, and weep: let your laughter be turned to mourning, and your joy to heaviness.
10 Humble yourselves in the sight of the Lord, and he shall lift you up.

We are assured God will keep us, when we do these things.  No one will snatch us out of His hands when we’re abiding in Him.  But if we remain in continual willful sin, or if we renounce God totally, we can know that God’s patience with us has an end.   

How dangerous is it to believe the wrong thing about salvation?

Well, believing turns into doing.  That is why even looking at woman with lust is considered adultery.  From Hebrews 6:
“For it is impossible, in the case of those who have once been enlightened, who have tasted the heavenly gift, and have shared in the Holy Spirit, and have tasted the goodness of the word of God and the powers of the age to come, and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt.”

That’s just terrifying!  Impossible to restore them to repentance?  And there are warnings elsewhere about branches being cut off and the lukewarm being vomited out of Jesus’ mouth.  So I would say it was dangerous to believe the wrong thing about salvation.  

How can we know for sure that we believe the right thing?

Be a Berean and search the scriptures yourself (as the person did in the video I transcribed).  Compare the evidence for once saved always saved, and the evidence against it.  Pray and ask for answers.  

[Here were the links from my letter:
https://bibleprophecytalk.com/i-was-wrong-about-once-saved-always-saved-and-my-backsliding-testimony/
https://bibleprophecytalk.com/more-thoughts-on-once-saved-always-saved/

https://www.instagram.com/p/Cu2wZikMqNr/  ]

Conversely, how can we know for sure if we are maybe believing the wrong thing?

Same as above mostly.  You could also examine the fruit of both ways of living.  Is believing in Once Saved Always Saved leading people to believe they can live in perpetual sin and still go to heaven?  I weep when I hear OSAS teachers say things like you can take the mark of the beast and still go to heaven.  I weep when I hear them say that you absolutely should not repent after you’ve been saved.  

May you all abound in the Love of God and in good works,
Kat