Blessed be the God and Father of our Lord Jesus Christ, who according to His great mercy has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead, to obtain an inheritance which is imperishable and undefiled and will not fade away, reserved in heaven for you, who are protected by the power of God through faith for a salvation ready to be revealed in the last time. (I Peter 1:3-5)
For if we sin willfully after we have received the knowledge of the truth, there no longer remains a sacrifice for sins, but a certain fearful expectation of judgment, and fiery indignation which will devour the adversaries. Anyone who has rejected Moses law dies without mercy on the testimony of two or three witnesses. Of how much worse punishment, do you suppose, will he be thought worthy who has trampled the Son of God underfoot, counted the blood of the covenant by which he was sanctified a common thing, and insulted the Spirit of grace? For we know Him who said, Vengeance is Mine, I will repay, says the Lord. And again, The Lord will judge His people. It is a fearful thing to fall into the hands of the living God. -- Hebrews 10:26-31
In context, the "deliberate sin" he's talking about is apostasy (return to Judaism) motivated by cowardice. But the point stands that it's possible to fall away.
Therefore let him who thinks he stands take heed lest he fall. -- 1 Cor 10:12
(All citations from the NKJV.)
You just can’t run out of Bible passages in threads like this:)
Well said...