The real argument is not about obtaining and losing salvation. That is sideshow of distraction, that no one takes seriously.
It is about being saved by grace through faith, or through faith only. Faith only being dead, because it is along and without God.
There is no believing Jesus without obeying Jesus, because believing Him is obeying Him, and so His eternal salvation is for all them that believe to obey Him.
If we are not obeying Him, we are not believing Him, and eternal salvation is not for us.
What is not of ourselves, is the faith of Jesus, which is the gift of God that saves, because the faith of Jesus obeys Him.
What is of ourselves is a salvation by faith only, where we are saved only because we believe we are saved, which has nothing to do with Scripture.
And we know that the Son of God is come, and hath given us an understanding, that we may know him that is true, and we are in him that is true, even in his Son Jesus Christ. This is the true God, and eternal life.
Them that believe Jesus, obey Jesus, and they have an understanding given to them by the gift of Jesus: His faith. Which is the understanding that there is no faith of Jesus without obeying Him.
Salvation by grace is not by faith only. That is not Scripture, nor teaching of Scripture, but is contrary to Scripture.
The eternal salvation of Jesus is by grace for them that obey Him, because they believe Him, not by works of our own righteousness without His faith, but by grace in obedience to His faith.
Believing in salvation is not believing Jesus.
Believing Jesus is obeying Jesus, but believing in salvation is believing we are saved only, which has nothing to do with being saved by believing and obeying Jesus, whereby we know we have eternal life.
With Jesus, believing is obeying, and not obeying is not believing, and unbelief is death:
Thou believest that there is one God; thou doest well: the devils also believe, and tremble.
Yea, a man may say, Thou hast faith, and I have works: shew me thy faith without thy works, and I will shew thee my faith by my works.
Show us a believer only, believing in salvation by faith only, and we will see a dead believer of faith only.
Salvation by grace through faith only is a myth and a devilish lie, used only to separate faith from works of faith, which is dead faith that does not save.
Salvation by grace through the gift of faith of God, is not anathema to works, but is the surety of obedience to God, by which we are justified with God and called a Friend of God, as Abraham was by works.
There is no salvation of God, standing 'isolated' from works of faith of God. The salvation of God is not eternally and graciously aloof from obedience to God. It is not a salvation by grace that cannot be 'touched' by sins of disobedience. That is a mystical salvation of an idolized grace, separated from God and His faith that obeys Him:
Little children, keep yourselves from idols. Amen.
Now, if someone wants to dispute eternal security of them that continue to believe and obey the Lord unto the end. I won't argue with it.
"But that's not possible!! Who then can be saved unto the end??"
With God all things are possible, and with God nothing shall be impossible, but without obedience to God nothing is possible, especially not salvation.
Who argues against obedience to the faith of our salvation, for eternal salvation to them that obey??
The disobedient, of course.