Blasphemy in the New Testament
There are three words in the Greek New Testament that all translate blasphemy. These words are often directed against God Himself. The Antichrist will commit the most outrageous acts of blasphemy against God. Revelation 13:6 tells us, He opened his mouth in blasphemies against God, to blaspheme His name. At other times the blasphemy can be directed at people. Paul and Silas were blasphemed as they tried to reason with the Jews out of the Scriptures. Acts 18:6,
But when they resisted and blasphemed, he shook out his garments and said to them, “Your blood be on your own heads!”
These Jews were cursing and insulting Paul and Silas in their disdain for the Gospel message.
Blasphemy Against the Holy Spirit
28 “Assuredly, I say to you, all sins will be forgiven the sons of men, and whatever blasphemies they may utter; 29 but he who blasphemes against the Holy Spirit never has forgiveness, but is subject to eternal condemnation”– 30 because they said, “He has an unclean spirit.”Some people think they have done this and are terrified. But this is not referring to taking the Lord’s name in vain, or murder, or unbelief, or criticizing “Christian Ministries.” Rather it is referring to only those religious leaders who saw Jesus perform astonishing miracles but with full conscious minds looked at those miracles and concluded that they were performed by the powers of darkness. Those religious leaders had the special privilege of being alive and witnessing the awesome miracles of Jesus, but they rejected them and attributed them to a demon spirit. That was the unpardonable sin and those who did this will spend eternity in hell.
Instructions for the Believer
Blaspheme has no part in the Christian’s life. Titus 3:2 warns, to malign no one, this word “malign” is the same Greek word for blasphemy. Those who malign and curse others or take the Lord’s name in vain are acting as nonbelievers. This sin is grounds for excommunication from the church (1 Timothy 1:20). You find this sin in two of the lists of sins in the New Testament (Mark 7:21-22; 2 Timothy 3:2). In contrast to this, Ephesians 4:29 tells us about the tone of our speech,
Let no unwholesome word proceed from your mouth, but only such a word as is good for edification according to the need of the moment, so that it will give grace to those who hear.
Scripture Reference

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Apocrypha
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