26For if we go on sinning deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins,
27 but a fearful expectation of judgment, and a fury of fire that will consume the adversaries. 28 Anyone who has set aside the law of Moses dies without mercy on the evidence of two or three witnesses. 29 How much worse punishment, do you think, will be deserved by the one who has trampled underfoot the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace? 30 For we know him who said, “Vengeance is mine; I will repay.” And again, “The Lord will judge his people.” 31 It is a fearful thing to fall into the hands of the living God.
-First, what ever this passage means, it is not talking about regular old sin, if it were we would all be LOST. 1 John 1:8-10 If we say that we have no sin, we deceive ourselves, and the truth is not in us. 9 If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. 10 If we say that we have not sinned, we make Him a liar, and His word is not in us.
-In the context of the book of Hebrews: --We are shown that Jesus is superior to angels and the Torah. --Jesus is superior to Moses --Jesus is superior to the Levitic priesthood, He is a priest after the order of Melchizedek --Jesus has supplied the perfect sacrifice which provides not just a covering for our sin, but access to the heavenly Holy of Holies.
-To reject this perfect sacrifice is THE SIN in verse 26, if it worries you, it should, But If You Are Worried About It, You Have Not Done It. This sin involves deliberately turning away from the perfect sacrifice and turning to something else.
-Salvation is about believing loyalty, there are no baal worshipers in heaven.
Michael Heiser Once Saved, Always Saved? Eternal security? Can a Christian lose salvation?