Were there any major scholars who DIDN'T believe all muslims would eventually attain paradise?

Question

The orthodox view from what I understand it, is that all muslims will ultimately enter heaven, even if it requires a period of chastisement.

Were there any major scholars who disagreed with this, who believed some muslims would be in hellfire for an eternity?

Answer 1

I'd say no, I never heard of a trusted scholar that espouses this view. There is no mainstream or even a common Islamic view that one who dies as a believer will be in hell forever if they do go to hell. That is because of what the Quran and hadiths tells us.

In the Quran, it says:

Source	Ayat
22:14	Indeed, Allah will admit those who believe and do good into Gardens, under which rivers flow. Surely Allah does what He wills.
9:72	Allah has promised the believers, both men and women, Gardens under which rivers flow, to stay there forever, and splendid homes in the Gardens of Eternity, and—above all—the pleasure of Allah. That is ˹truly˺ the ultimate triumph.
85:11	Surely those who believe and do good will have Gardens under which rivers flow. That is the greatest triumph.
10:19	Surely those who believe and do good, their Lord will guide them ˹to Paradise˺ through their faith, rivers will flow under their feet in the Gardens of Bliss
14:23	Those who believe and do good will be admitted into Gardens, under which rivers flow—to stay there forever by the Will of their Lord—where they will be greeted with “Peace!”

There are much more verses that share the same message throughout the Quran about the believers entering paradise as you can check out here:

https://quran.com/search?page=1&q=Gardens%20under%20which%20rivers%20flow&translations=131

Hadiths

Sahih Bukhari 6560

Narrated Abu Sa`id Al-Khudri: Allah's Messenger (ﷺ) said, "When the people of Paradise have entered Paradise, and the people of the Fire have entered the Fire, Allah will say. 'Take out (of the Fire) whoever has got faith equal to a mustard seed in his heart.' They will come out, and by that time they would have burnt and became like coal, and then they will be thrown into the river of Al-Hayyat (life) and they will spring up just as a seed grows on the bank of a rainwater stream." The Prophet (ﷺ) said, "Don't you see that the germinating seed comes out yellow and twisted?"

So those who have a mustard seed of faith in their hearts will eventually go to heaven and will not abide in hell forever if they were in hell in the first place.

Conclusion

In the Quran, it tells us repeatedly that those who believe and do good are the ones that enter paradise forever. Meaning the believers will enter paradise and abide therein for all eternity. The hadith tells us that no believer stays in hell forever.

If there happens to be someone who is known as Muslim but does not truly believe in Islam and might believe in another religion or might believe in Islam but believe in another deity alongside Allah, do you think they are believers according to Islam? Ultimately that is for Allah (SWT) to decide as judgement belongs to him and him alone.

Answer 2

There were no notable orthodox sunni scholars who held such a view. A general negation is claimed by various scholars such as:

اتفق أهل السنة على أن المؤمن لا يخرج عن الإيمان بارتكاب شيء من الكبائر إذا لم يعتقد إباحتها، وإذا عمل شيئا منها، فمات قبل التوبة، لا يخلد في النار، كما جاء به الحديث، بل هو إلى الله، إن شاء عفا عنه، وإن شاء عاقبه بقدر ذنوبه، ثم أدخله الجنة برحمته

The Ahl al-Sunnah are in agreement that a believer is not taken out from faith by committing anything from the major sins as long as he does not disbelieve by consider the sin to be lawful. And that if he does any of them (major sins) and dies without repentance, then he shall not be in hell forever, rather he is subject to the will of Allah, if Allah wills he may be forgiven, and if Allah wills he will be punished to the extent of his sin and then admitted into paradise because of Allah's mercy.

^{— Sharh al-Sunnah - Baghawi}

إجماع أهل الحق على أن الزاني والسارق والقاتل وغيرهم من أصحاب الكبائر غير الشرك لا يكفرون بذلك بل هم مؤمنون ناقصو الإيمان إن تابوا سقطت عقوبتهم وإن ماتوا مصرين على الكبائر كانوا في المشيئة فان شاء الله تعالى عفا عنهم وأدخلهم الجنة أولا وإن شاء عذبهم ثم أدخلهم الجنة

[meaning is the same as above]

^{— Sharah Nawawi}

However some of the sects other than the Ahl al-Sunnah, such as some of the Khawarij, the Muʿtazilah and Zaydi Shias differ on this.