Blasphemy, meaning injurious speaking, dishonors God or sacred things, whether deliberately or not. Every blasphemy can be forgiven except blasphemy against the Holy Spirit (Matthew 12:31-32), which requires deliberate, sustained opposition by one who was enlightened, received the Spirit, and repented, then willfully fell away (Hebrews 6:4-8; 10:26-29). Blasphemy, like cursing, swearing, and profanity, reflects the pride the Greeks called hubris, which drove Satan to defy God, and the Third Commandment forbids it (Exodus 20:7). Believers must guard their minds and avoid foul language. Hatred of God, expressed through blasphemy, drives Marxism and will mark the end-time beast, who blasphemes God's name, His tabernacle, and those in heaven, while plague-stricken men blaspheme God and refuse to repent. Also see sermons and articles about Blasphemy.
Mark 3:28-29 'Assuredly, I say to you, all sins will be forgiven the sons of men, and whatever blasphemies they may utter; but he who blasphemes against the Holy Spirit never has forgiveness, but is subject to eternal condemnation"
Matthew 12:31-32 “Therefore I say to you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men. Anyone who speaks a word against the Son of Man, it will be forgiven him; but whoever speaks against the Holy Spirit, it will not be forgiven him, either in this age or in the age to come.
Hebrews 10:28-29 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?
Leviticus 24:16 And whoever blasphemes the name of the LORD shall surely be put to death. All the congregation shall certainly stone him, the stranger as well as him who is born in the land. When he blasphemes the name of the LORD, he shall be put to death.
Matthew 12:24 Now when the Pharisees heard it they said, “This fellow does not cast out demons except by Beelzebub, the ruler of the demons.”
Matthew 26:63-65 But Jesus kept silent. And the high priest answered and said to Him, "I put You under oath by the living God: Tell us if You are the Christ, the Son of God!" Jesus said to him, "It is as you said. Nevertheless, I say to you, hereafter you will see the Son of Man sitting at the right hand of the Power, and coming on the clouds of heaven." Then the high priest tore his clothes, saying, "He has spoken blasphemy! What further need do we have of witnesses? Look, now you have heard His blasphemy!
Mark 14:64 You have heard the blasphemy! What do you think?” And they all condemned Him to be deserving of death.
John 10:33-36 The Jews answered Him, saying, “For a good work we do not stone You, but for blasphemy, and because You, being a Man, make Yourself God.” Jesus answered them, “Is it not written in your law, ‘I said, “You are gods”’? If He called them gods, to whom the word of God came (and the Scripture cannot be broken), do you say of Him whom the Father sanctified and sent into the world, ‘You are blaspheming,’ because I said, ‘I am the Son of God’?