Hujjah

Itmām al-hujjah (Arabic: اتمام الحجة‎‎ "completion of proof", from itmāmu "completion, realization" and ḥuǧǧatu "pretext, proof") is an Islamic concept denoting that religious truth has been completely clarified by a Messenger of Allah and made available to a people, who are considered to have no excuse to deny it.

The concept of Itmām al-hujjah requires that religious truth is presented by a Rasul (Messenger) and not by a mere Nabi (Prophet). The former is distinguished from the latter by having received a message for a community in the form of a book and by being assured success. While all messengers are prophets, not all prophets are messengers. In Shiite Islam, an Imam can also be hujjah through whom Allah's presence becomes established for a believer.

The Qu'ran asserts that after Itmām al-hujjah has been attained, those rejecting the religious truth have no excuse and are punished by Allah.

This punishment is considered to occur both in this world and the next world. The judgment in this world is considered a rehearsal for the ultimate punishment or reward on the Day of Judgement.

The Qur'an explains this punishment in the following verse:

And the disbelievers said to their Messengers: ‘‘We will drive you out of our land, or you return to our religion’’. But their Lord inspired [this message] to them [the Messengers]: ‘‘Verily We will cause the wrong-doers to perish! And verily We will cause you to abide in the land, and succeed them. This is for those who feared the time when they shall stand before My tribunal and those who feared My warnings’’. ^{[Quran 14:9–14]}

Generally, the punishment is considered to come either through natural disaster or through human hands.

Punishment comes through natural calamities, if the Messenger has very few companions and no place to migrate.

Examples in the Qur’an are the nations of Noah, Lot, Saleh, and Shoaib along with some other nations of Messengers, which were punished in the form of raging storms, cyclones and other calamities, which completely destroyed them. A notable exception would be the "People of the Book", who as monotheists were not destroyed but reduced to a subjugated status. The Israelites are considered punished by "constant subjugation to the followers of Jesus till the Day of Judgement". The Qur'an explains:

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