8 Bible Verses about Unforgivable Sin

For this I say to you, All sin and blasphemy shall be let go to men; but the blasphemy of the Spirit shall not be let go to men. And whoever speaks a word against the Son of man, it shall be remitted to him; but whoever speaks against the Holy Spirit, it shall not be let go to him, neither in this time, nor that about to be.

Truly I say to you, That all sins shall be remitted to the sons of men, and defamations whatever they defame: And whoever should defame against the Holy Spirit has no remission forever, but he is liable to the penalty of eternal condemnation.

And every one who shall say a word against the Son of man, it shall be remitted to him: and to him blaspheming against the Holy Spirit, it shall not be remitted.

For we sinning voluntarily after receiving the knowledge of the truth, there is left no more a sacrifice for sins, But a certain terrible expectation of judgment and jealousy of fire, being about to devour the adversaries. Any one having rejected Moses' law, without compassion dies by two or three witnesses:read more.
Of how much worse punishment, think ye, shall he be deemed worthy. having trodden down the Son of God, and deemed the blood of the covenant common, in which he was consecrated, and having outraged the Spirit of grace?

For they said, He has an unclean spirit.

But the Pharisees, having heard, said, He casts not out demons, but by Beelzebub, ruler of demons.

And the scribes, they having come down from Jerusalem, said, That he has Beelzeboul, and that by the ruler of demons he casts out demons.

And certain of them said, By Beelzebul ruler of demons he casts out demons.