Everlasting existence bequeathed to the undeserving but continuously faith-exercising confessing soul is without end, no matter what.
On the other hand, if one says that he believes, but continues to lead a carnal life-style without change, then it is he that is the liar, not the Jesus of the Bible.
And the one insisting that you can lose your salvation--and with it eternal life with God--s the perpetrator of a false gospel that cannot utterly remove the guilt of one's sin.
I hear ya...
1 Corinthians 9:27
No, I strike a blow to my body and make it my slave so that after I have preached to others, I myself will not be disqualified for the prize.