While I haven't participated heavily in discussions like that in quite a while, and while it would take too long to share all of what was discussed in those discussions, I'll highlight one of the main questions I used to ask people who worried or feared about the "loss" of salvation: "What exactly is it that saves a person in the first place?"
Paul put it quite simply:
For by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast (Eph 2:8-9)
How much of that is your work? How much of it is "of yourselves?" None of it! It's "the gift of God, not by works..."
So then, once we're saved, does it suddenly become "of ourselves" to keep ourselves saved? For the many people who are so worried about Christians losing their salvation, it would seem that there's more than just an ounce of that type of thinking going around in their heads.
To lead up to where I'm going with this, let me relate that type of thinking to receiving some sort of gift that doesn't come with the batteries. Sure, the gift is free, but it's up to you to continuously provide the batteries to make sure the gift remains in working order.
But that's not the type of gift God has given us! God has not simply given us the gift of salvation, and then left us alone to try to maintain it our own. He has included Himself - His very Life - in the package!
It was His life that saved us, and it's His life that keeps us!
Unfortunately a very deficient "gospel" has been spread, and keeps on being spread, in which grace and salvation are depicted merely as a matter of our sins being forgiven. It's great that our sins have been forgiven, but if you are forgiven and yet remain in the same condition, what good is that? What's missing from the gospel message that's commonly taught is the issue of LIFE! We've not only been forgiven of all sin, but our sin has been taken away and we died to our old life in Adam, and we were raised up and made alive together with Christ Himself! Not only have we been forgiven, but our condition has changed! In Adam we were dead to God, but in Christ we are now fully alive to God.
Paul's words that follow the words quoted above say that we are God's workmanship. It's all of Him. Getting saved is of Him and not of us. Remaining saved is also of Him and not of us. If you couldn't get yourself saved, what can you do to keep yourself saved??? Trust Him to keep you.
"God... even when we were dead in trespasses, made us alive together with Christ..." (Eph 2:4-5). If He made you alive even when you were dead in your trespasses, do you think for a moment that He's going to not keep you alive when you sin now? While you can do nothing to keep yourself, He can and does continuously supply you with His very life, because as a branch is continuously sustained, not in and of itself but by the life of the vine, you are also continuously sustained by the very life of the One who calls Himself the Vine, Jesus.