In the Name of Allaah, the Most Gracious, the Ever Merciful…
The famous fifth-century medical expert and philosopher, Ibn Sina, known to the West as “Avicenna”, is often credited as being one of the greatest Muslim scientists in history. His name is a celebrated one in many Muslim circles, and even hospitals and institutions of learning are named after him out of respect and admiration for his achievements.
While many Muslim scientists throughout history truly did pioneer many important medical and scientific breakthroughs, Muslims need to step back and re-examine what they have been led to believe about Ibn Sina specifically – Is it factually correct? Was he even a Muslim?
Shaykh al-Islaam Ibn Taymiyyah on Ibn Sina
Aboo ‘Alee Al-Husayn ibn ‘Abdillaah ibn al-Hasan ibn ‘Alee ibn Sina (d.428) was born to a severely deviant Ismaa’eelee (Shiite) family, known for their severe blasphemy and hypocrisy, as mentioned by Shaykh al-Islaam Ibn Taymiyyah. In fact, as Ibn Taymiyyah said:
وأحسن ما يُظهرون دين الرفض وهم في الباطن يُبطنون الكفر المحض
“The best thing they showed openly was ar-Rafdh (being Raafhidah Shiites), while they concealed pure, absolute disbelief inwardly.” 
Ibn Taymiyyah confirmed this by mentioning that Ibn Sina himself identified his own family, his father, and his brother to all be from this severely deviant group that was exposed and declared outside of Islam by many scholars.
Ibn Taymiyyah further detailed how Ibn Sina attempted to blend what he learned from the deviant claimants to Islam, the Mu’tazliah and Raafidhah, with the polytheistic philosophy of Aristotle, and when he did so he deviated even further, inventing new sets of beliefs so blasphemous that they surpassed some of the falsehood of the Jahmiyyah and even the pagan philosophers themselves! 
After listing a number of Ibn Sina’s philosophical deviations, Ibn Taymiyyah went on to say:
لا يقوله إلا من هو من أجهل الناس وأضلهم وأشبههم بالبهائم من الحيوان
No one says these things other than the most ignorant of people, the most astray, and those who most resemble farm animals! 
The Great Scholar Ibn al-Qayyim on Ibn Sina
And the great scholar, Ibn Qayyim al-Jowziyyah, said:
He (Ibn Sina) was from the Qaraamitah Baatiniyyah [Sect], those who do not believe in a beginning (of the creation) nor an end, nor do they believe in a Lord of the creation, nor any prophet sent from Allaah, the Most High.
Such deviant hypocrites (zanaadiqah) pretend to be Raafidhah, whilst they conceal pure, absolute disbelief inwardly, claiming to be descendants of the family of the Messenger (may Allaah raise his rank and grant him and his family peace). He and his family are all free of them in terms of both lineage and religion… 
Ibn al-Qayyim also referred to Ibn Sina as the imaam of the severe deviants (إمام الملحدين), and said, “This deviant and his followers are disbelievers in Allaah, the Angels, the Books, the Messengers, and the Last Day.”  Read this article to find out how he came to this conclusion.
Comparing Ibn Sina’s and other philosophers’ disbelief to that of the pagan Arabs of pre-Islamic Makkah, he concluded that the beliefs of the pagan Arabs were less offensive than the beliefs of Ibn Sina and the philosophers. 
He further compared the blasphemy of the most deviant of the Jahmiyyah cults to the ideas of Ibn Sina and concluded that Ibn Sina’s beliefs were even more deviant.
After explaining how Ibn Sina denied basic pillars of belief, he concluded with the verdict:
فالرجل معطل مشرك جاحد للنبوات والمعاد، لا مبدأ عنده، ولا معاد، ولا رسول ولا كتاب
The man was a denier (of Allaah’s Attributes), a polytheist, a rejecter of matters related to prophethood and the Ma’aad (the Last Day), having no belief in the beginning or end of creation, nor any belief in a messenger or a book. 
For those who wish for more specific information on the heretical blasphemy of Ibn Sina, they are welcome to investigate the detailed documentation of how he rejected each pillar of Faith, one by one, explained by Ibn al-Qayyim himself. 
Other Scholars on Ibn Sina
Ibn Hajr quotes an early Shaafi’ee scholar, Ibn Abid-Damm al-Hamawee, as saying:
All the scholars have agreed that Ibn Sina held that the universe was infinite and there would be no physical resurrection, while he did not reject (the concept of) a spiritual resurrection, and that he is reported to have said that Allaah does not know every detailed piece of knowledge, rather He knows things in general.
Thus, the scholars of his time and those after him whose statements are relied upon in all matters have spoken decisively about his disbelief and the disbelief of Aboo Nasr al-Farabi as well, due to their positions on these matters in contradiction to the beliefs of the Muslims. 
One of today’s senior scholars, a member of the Permanent Committee for Research and Fatwaa in Saudi Arabia, Shaykh Saalih al-Fowzaan (may Allaah preserve him), was asked about someone who praises Ibn Sina and lists him among the scholars of Islam. He replied:
He is one of two cases:
1. He may be ignorant, and thus he does not know about the condition of Ibn Sina. Such a person has no right to speak, rather he must keep silent.
2. Or perhaps he knows about Ibn Sina and his teachings of disbelief and he agrees with him, praising him for that reason. In this case, his ruling is the same ruling as Ibn Sina (i.e. disbeliever), and refuge with Allah is sought. This is because he has agreed with him and praised him for that (his disbelief).
So this is a very serious issue!
However, some people may praise Ibn Sina strictly because he was a doctor. This is a worldly profession, and he was really a doctor. However, there were many non-Muslim doctors more proficient in the medical field than him, so why the specific focus on Ibn Sina? They say: “Because he ascribed to Islam, and so this is something for Muslims to be proud of.”
We say: Islam is free from him, and Islam does not need him!
To conclude: He is not to be praised or spoken of highly because he was one of the Baatiniyyah [Cult], a severely deviant philosopher who claimed that the universe may be infinite (having no beginning or end). 
Also, Shaykh ‘Abdul-‘Azeez ar-Raajihee explained why Muslims who know about him are required to consider him a disbeliever. [click here]
Naming Schools and Hospitals After Ibn Sina?
Additionally, Shaykh Saalih al-Fowzaan, Shaykh Ibn ‘Uthaymeen, and others mentioned that it is not permissible to name schools, hospitals, or health clinics after him (in his honor). [click here]
Modern Attempts to Include Ibn Sina Among the Muslim Scientists
Muslims today may come across unreliable websites and other sources of misinformation claiming that Ibn Sina was a great Muslim scientist and/or scholar. Some clinics and schools in the Muslim lands are even named after him to honor him, which is not permissible, as mentioned by Shaykh Saalih al-Fowzaan.
What exactly is the cause of this serious mistake? It could be rooted in one or any number of the following causes:
- Speaking / writing about matters without knowledge of the Religion
- Passing on information carelessly
- Intended promotion of the Shiite Religion
- Intended promotion of philosophy as an Islamic science
- Gross neglect or total lack of concern for issues of ‘aqeedah (belief)
- Blind ambition to please everyone
- Justifying what people have already said or written
Muslims who have mistakenly praised this severely deviant disbelieving philosopher, Ibn Sina, are urged to hasten to repent to Allah and free themselves of this serious error, lest they be counted alongside of Ibn Sina as a disbeliever in this life and the Next, and refuge with Allaah is sought.
And Allaah knows best.
Written by: Moosaa Richardson
 ar-Radd ‘alal-Muntiqiyyeen (pp.141-142), Majmoo’ al-Fataawee (9/134)
 ar-Radd ‘alal-Mantiqiyyeen (pp.143-146), Majmoo’ al-Fataawee (9/135-138)
 Dar’ Ta’aarud al-‘Aql wan-Naql (5/65)
 Eghaathat al-Lah-faan (2/286, checking of Muhammad Haamid Faqee)
 Eghaathat al-Lah-faan (2/287, checking of Muhammad Haamid Faqee)
 Eghaathat al-Lah-faan (2/288, checking of Muhammad Haamid Faqee)
 Eghaathat al-Lah-faan (2/280, checking of Muhammad Haamid Faqee)
 Eghaathat al-Lah-faan (2/282, checking of Muhammad Haamid Faqee)
 Eghaathat al-Lah-faan (2/279-282, checking of Muhammad Haamid Faqee)
 Lisaan al-Meezaan (2/293)
 At-Ta’leeq al-Mukhtasir ‘alal-Qaseedah an-Nooniyyah (3/1328). (Arabic)