Blasphemy, as defined in some religions or religion-based laws, is an insult that shows contempt, disrespect or lack of reverence concerning a deity, an object considered sacred or something considered inviolable. Some religions regard blasphemy as a religious crime, especially the Abrahamic religions, including insulting the Islamic prophet Muhammad in Islam, speaking the "sacred name" in Judaism, and the "eternal sin" in Christianity.
In the early history of the Church, blasphemy "was considered to show active disrespect to God and to involve the use of profane cursing or mockery of his powers". In the medieval world, those who committed blasphemy were seen as needing discipline. By the 17th century, several historically Christian countries had legislation against blasphemy. Blasphemy laws were abolished in England and Wales in 2008, and in Ireland in 2020. Scotland repealed its blasphemy laws in 2021. Many other countries have abolished blasphemy laws including Denmark, the Netherlands, Iceland, Norway and New Zealand. , 40 percent of the world's countries still had blasphemy laws on the books, including 18 countries in the Middle East and North Africa, or 90% of countries in that region. Dharmic religions, such as Hinduism, Buddhism and Jainism, have no concept of blasphemy and hence prescribe no punishment.
The word "blasphemy" came via Middle English blasfemen and Old French blasfemer and Late Latin blasphemare from Greek βλασφημέω, from βλασ, "injure" and φήμη, "utterance, talk, speech". From blasphemare also came Old French blasmer, from which the English word "blame" came. Blasphemy: 'from Gk. blasphemia "a speaking ill, impious speech, slander," from blasphemein "to speak evil of." "In the sense of speaking evil of God this word is found in Ps. 74:18; Isa. 52:5; Rom. 2:24; Rev. 13:1, 6; 16:9, 11, 21. It denotes also any kind of calumny, or evil-speaking, or abuse (1 Kings 21:10 LXX; Acts 13:45; 18:6, etc.)."
In the early history of the Church, blasphemy "was considered to show active disrespect to God and to involve the use of profane cursing or mockery of his powers".