What is the major religion in Oman?

Answer 1

The state religion of Oman is a sect of Islam called Ibadi.

It is of those descended from the Kharawij (those who at first supported Ali bin Abi Talib, the fourth and final rightly-guided Khalifa, and then rejected him, and thus step outside of the Sunni-Shi'a dichotomy).

The Khawarij have a few distinct differences from Sunni Islam. The most distinct difference is the doctrine that a sinner, who commits a major sin (shirk [idolatry], zina [adultery and fornication], etc.), is no longer a Muslim, and is condemned to the Fire of Hell for all eternity. Orthodox Islam holds that if a Muslim commits a major sin, he is a major sinner, but He is still a Muslim as long as he believes the Shahadah (There is no deity but God, and Muhammad sall'Allahu alayhi WA salam is His Messenger), disregarding some Salafis who believe that "A believer who drinks is not a believer while he is drinking, a believer who adulters or fornicates is not a believer while he is committing illegal sexual intercourse" (Sahih Bukhari).

Whereas it is the doctrine of Orthodox Islam that the Hellfire has atoning or purifying properties, so that anyone who dies believing in his heart that there is no deity but God, and Muhammad (sall'Allahu alayhi WA salam) is the Messenger of God, will eventually be redeemed from the Hellfire (cf. the Roman Catholic concept of purgatory).

Answer 2

Islam, although other religions are practiced freely.

Answer 3

Islam is the state religion.

Answer 4

Islam is Oman's main religions.