What is the Truth? Let the Scripture speak for itself!
Salvation can be neglected:
"...we must pay much closer attention to what we have heard, lest we drift away from it. For if the word spoken through angels proved stead-fast, and every transgression and disobedience received a just recompense, how shall we escape if we neglect so great a salvation?"
Salvation can be lost:
"In the case of those who have been once enlightened and have tasted of the heavenly gift and have been made partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, and then have fallen away, it is impossible to renew them again to repentance, since they again crucify to themselves the Son of God, and put Him to open shame."
"For if after they have escaped the defilements of the world by the knowledge of the Lord Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first. For it would have been better for them not to have known the way of righteousness, than having known it, to turn away from the holy commandment delivered to them. It has happened to them according to a true proverb, 'A dog returns to it own vomit,' and 'a sow, after washing, returns to wallowing in the mire.'"
2 Peter 2:20-22
"For if we go on sinning willfully after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, but a certain terrifying expectation of judgment..."
Hebrews 10:26, 27
Salvation is a work in progress:
"So then... work out your salvation with fear and trembling; for it is God who is at work in you, both to will and to work for His good pleasure."
"For I am confident of this very thing, that He who began a good work in you will perfect it until the day of Christ Jesus."
"For you have need of endurance, so that when you have done the will of God, you may receive the promise."
"And you will be hated by all on account of My name, but it is the one who endures to the end who will be saved."
"For yet in a little while, He who is coming will come, and will not delay. But My righteous one shall live by faith; and if he shrinks back, My soul has no pleasure in Him."
"...God has chosen you in the beginning for salvation in sanctification of the Spirit and faith in the truth. And it was for this He called you through the gospel to the gaining of the glory of our Lord Jesus Christ."
1 Thessalonians 2:13, 14
Instruction and discipline:
"For the grace of God has appeared to all men, bringing salvation, instructing (or disciplining) us to deny ungodliness and worldly desires and to live sensibly, righteously and godly in the present age; looking for the blessed hope and the appearing of the glory of the Great God and Savior, Christ Jesus; who gave Himself for us, that He might redeem us from every lawless deed and purify for Himself a people for His own possession, zealous for good deeds. These things speak and exhort and reprove with all authority."
"...although he was a Son He learned obedience from the things which He suffered; and having been made perfect, He became to all those who obey Him the source of eternal salvation; being designated by God as a high priest according to the order of Melchizedek."
"But when the kindness of God our Savior and His love for mankind appeared, He saved us, not on the basis of deeds which we have done in righteousness, but according to His mercy, by the washing of regeneration and renewing by the Holy Spirit, whom He poured out upon us richly through Jesus Christ Our Savior, that being justified by His grace we might be made heirs according to the hope of eternal life."
Once saved, always saved? I don't think so!