They are broken off from fellowship with God. They do not lose salvation, they lose their communion.
It is too bad you are bound to fear.
“They are broken off from fellowship with God. They do not lose salvation, they lose their communion.”
Hmmmm....”there can be no further sacrifice for sin for us but only a terrifying expectation of judgment and the fire of God’s indignation, which will one day consume all that sets itself against him. The man who showed contempt for Moses’ Law died without hope of appeal on the evidence of two or three of his fellows. How much more dreadful a punishment will he be thought to deserve who has poured scorn on the Son of God, treated like dirt the blood of the agreement which had once made him holy, and insulted the very Spirit of grace?”
I think that goes beyond “broken communion”!
“It is too bad you are bound to fear.”
“The Bible repeatedly calls people to fear God. In Psalm 111:10 the psalmist declared that “the fear of the Lord is the beginning of wisdom” (cf. Prov. 1:7; 9:10), while Proverbs 23:17 commands, “Live in the fear of the Lord always.” A wise father counsels his son to “fear the Lord and the king” (Prov. 24:21), while Peter exhorted his readers to “Honor all people, love the brotherhood, fear God, honor the king” (1 Pet. 2:17). In Matthew 10:28 Jesus warned, “Do not fear those who kill the body but are unable to kill the soul; but rather fear Him who is able to destroy both soul and body in hell.” To fear God is to live in the reality of His holiness, His sovereignty, and His judgment of sin. It is to love God, respect Him, reverence Him, adore Him, hold Him in awe, and worship Him. And that can only be done by loving His Son the Savior (John 5:23).”
https://www.gty.org/library/bibleqnas-library/QA0058/fear-god-with-all-your-heart
“The response of a true worshiper to a vision of God should resemble Isaiah’s. We should be overwhelmed with our own sinfulness and consequently consumed with a sense of holy terror. I am certain that if the people today who claim to have seen God really saw Him, they wouldn’t be lining up to get on the latest Christian talk show; they’d be lying prostrate on the ground, grieving over their sin.
Reverence and Godly Fear
A true worshiper comes into the presence of God with a healthy but soul-shattering fear. God does, after all, punish sin, even in those who are redeemed. Hebrews 12:6 reminds us, “Whom the Lord loves He disciplines, and He scourges every son whom He receives.”
Hebrews 12:28 goes on to say, “Let us have grace, whereby we may serve God acceptably with reverence and godly fear” (KJV). The word translated “serve” is latreuo, a word for worship. The writer is talking about acceptable worship, and he lists two key elements: “reverence and godly fear.” Note the reason he gives for such worship: “For our God is a consuming fire” (Hebrews 12:29).”
https://www.gty.org/library/blog/B160810/whatever-happened-to-the-fear-of-god
“Then you will say, “Branches were broken off so that I might be grafted in.” True enough; they were broken off by unbelief, but you stand by faith. Do not be arrogant, but be afraid. For if God did not spare the natural branches, He will not spare you either. Therefore, consider God’s kindness and severity: severity toward those who have fallen but God’s kindness toward you—if you remain in His kindness. Otherwise you too will be cut off. And even they, if they do not remain in unbelief, will be grafted in, because God has the power to graft them in again.”
The Jews boasted of being God’s Chosen People. But “they were broken off by unbelief”. It always returns to believing God. Once saved, always saved didn’t apply to God’s Chosen People, nor to us. Not if we quit believing.
Nothing to do with earning God’s approval by our good deeds. If we understood the holiness of God, we would never presume it was possible! It has nothing to do with us being good enough to merit God’s approval. But we are required to KEEP believing.