According to Islam, there are 70 major sins and a variety of minor sins. Within the list of major sins there are several sins that are unforgivable. Any sin is considered to be an act against the will of Allah, or God. Therefore, the weight of major sins is heavy and it is highly recommended that Muslims abstain from these acts.

Believing in Gods Other Than Allah

The first pillar or requirement of Islam is the declaration of faith, or Shahada. Muslims believe there is no god but Allah and Muhammad is His prophet. Worshiping other gods or even Muhammad and prophets as Allah is considered a major sin. Of the 70 major sins in Islam, this is the first sin and is called Shirk. The Quran states that all of creation comes from Allah and there is no being or thing more powerful than Allah.

Despair

Despair is considered the second major sin after Shirk. Someone who has lost faith and is hopeless has committed the sin of despair. When in this state, a person continues to commit evil deeds and already believes that he is destined for hell. Rather than repenting for his sins, he believes there is no benevolent being watching out for his own good. As a result, this person commits even more sins.

Murder

Murder is an unforgivable sin. Anyone who commits murder that is not under the authority of Allah commits a grave sin. Suicide is considered to be the same as murder. The Quran states that all non-believers who commit murder are subjected to eternal punishment in hell. If the murderer is a believer, he must repent and become subjected to the fate of the victim's heirs. They may choose to forgive or kill in retribution. If forgiven, the murderer must free a slave, feed 60 poor people and fast 60 times.

Magic

Magic is a major sin in Islam because it involves believing in a power other than Allah. Magic is a form of deception because the magician tricks the audience. Muslims also believe that magic is used to call upon demons for the sake of harming someone else. Using tarot cards, astrological charts and going to fortune tellers are all sins. Muhammad said that even he could not predict the future. Thus, any Muslim who engages in magic is committing a sin.