Who are the Al-Muwahhidoon (monotheists)?
All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Monotheism means dedicating worship only to Allaah The Almighty. It is the antonym of polytheism, which means worshipping other than Allaah The Almighty. This means that a monotheist is a person who sincerely devotes his worship to Allaah The Almighty alone. In the interpretation of the Saying of Allaah The Almighty (what means): {…and another slave belonging exclusively to one man….} [Quran 39:29], At-Tabari said that this refers to a monotheist who sincerely dedicates his worship to Allaah The Almighty alone and this is the cause of his entering Paradise.
On the authority of Abu Hurayrah the Prophet, sallallaahu ‘alayhi wa sallam, said that no one enters Paradise except a believing soul, [Al-Bukhari, Muslim] meaning, except a monotheist.
A person deprived of monotheism will also be deprived of Paradise. Allaah The Almighty Says (what means): {Indeed, he who associates others with Allaah - Allaah has forbidden him Paradise, and his refuge is the Fire. And there are not for the wrongdoers any helpers.} [Quran5:72]
Moreover, monotheism prevents a monotheist from eternally residing in Hell whereas polytheism causes a polytheist to reside there for eternity.
This is a brief abstract about monotheism and monotheists.
If you mean the state of Al-Muwahhidoon (the Monotheists), it is a state that existed in Morocco in the sixth century A.H. and it was founded by Muhammad ibn Tomart who is known as Al-Mahdi. He died in 524 A.H. For further information about this state, you can refer to history books.
Allaah Knows best.
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