Islamic Eschatology – Day of Judgment, Paradise & Hell Fire
Can there be a temporary hell?
In order to understand how Hell Fire could be temporary one has to understand the all-encompassing Mercy of Allah ﷻ. Few but very renowned religious authorities in Islam have understood and explained that the concept of hell fire is temporary. They interpreted it as such because Allah ﷻ placed special emphasis towards His attributes of All Pervading Grace (Al Rahman) and All Merciful (Al Raheem) as compared to other attributes in the Quran. As mentioned earlier that one of the prime reasons why Allah ﷻ created the entire universe is due to His grace and mercy as informed to us in a prophetic hadith: “When Allah created the creation, He wrote in the Book, which is with Him over His Throne: 'Verily, My Mercy prevails over My Wrath’” This teaches us that in Islam the purpose of Allah ﷻ to create entire universe is to have mercy and not punish. Since paradise is an expression of Allah’s mercy, similarly, hell fire is an expression of His anger, and His mercy will eventually prevail over His wrath in the hereafter. Allah ﷻ warns us of His punishment but reminds us that the mercy is even greater: “With my chastisement do I afflict whom I will - but My Grace overspreads everything.” Based on what is said in Quran and prophetic teachings about Allah’s immense mercy, some renowned Islamic authorities of the past shared the view that hell is temporary in references to similar verses in the Quran: "[But] He will say: “The fire shall be your abode, therein to abide - unless God wills it otherwise.” Verily, your Sustainer is wise, all-knowing." "Now as for those who [by their deeds] will have brought wretchedness upon themselves, [they shall live] in the fire, where they will have [nothing but] moans and sobs [to relieve their pain], therein to abide as long as the heavens and the earth endure - unless your Sustainer wills it otherwise: for, verily, your Sustainer is a sovereign doer of whatever He wills."
The wording “Unless Your Sustainer Wills it otherwise” and that “Your Sustainer is a sovereign doer of whatever He Wills” is an indication for us that as opposed to the perpetual bliss and happiness of paradise, the term in hell might be temporary. There is a hadith of the Prophet ﷺ, discussed earlier, that mentions about those who will be taken out from the hellfire after being thrown in to it and receiving their due punishment: “[On the Day of Judgment,] those who deserve paradise will enter paradise, and those who deserve the fire, the fire. Thereupon God, the Sublimely Exalted, will say, 'Take out [of the fire] everyone in whose heart there was as much of faith [or, in some versions, "as much of good"] as a grain of mustard seed!' And so they will be taken out of it, already blackened, and will be thrown into the River of Life; and then they will come to life [lit., 'sprout'] as a herb sprouts by the side of a stream: and did you not see how it comes out, yellow and budding?” 
One of the modern leading Islamic scholar Sheikh Hamza Yusuf in his book "Who are the disbelievers" mentions the views of two of the greatest medieval authorities of Islam namely Sheikh Muhiyuddin Ibn Arabi and Sheikh Ibn Taymiyyah, who held the view of temporary hell fire: “Both Shaykh Muhiyuddin Ibn Arabi and Ibn Taymiyyah held heterodoxic views concerning the Hellfire as a result of their attempts at reconciling divine mercy with the idea of infinite punishment for finite sins. In one transmission considered sound, Shaykh Ibn Taymiyyah inclined toward an Annihilationist view, which holds that eventually the fire is extinguished. The heretic Jahm b. Safwan also shared this view, and it is common among some Jewish ethicists. Shaykh Muhiyuddin Ibn Arabi held that eventually the people of the Fire become fire-like and no longer feel pain but actually come to enjoy the Fire.” However, in this same book, Sheikh Hamza does mention his own point of view to be in accordance the mainstream orthodox opinion in Islam which includes Imam Ghazzali that many would suffer eternally in hellfire and they would be those like satan who knowingly rejected the truth and were deeply engrossed in their arrogance. For this view, he shares the orthodox opinions and supports them with ahadith of the Prophet ﷺ such as: “Shall I not tell you who the denizens of the Fire are?” His companions replied, “Indeed, tell us.” He then said, “Every cruel, harsh, puffed up, miserly, arrogant one.” Also famous hadith, which is the first hadith transmitted to students of hadith, states, “Whoever shows no mercy will have no mercy shown [to him].”
Nevertheless, after reading views of Hamza Yusuf the following hadith of the Prophet ﷺ came to my mind: “Whoever has a mustard seed's weight of pride (arrogance) in his heart, shall not be admitted into Paradise. And whoever has a mustard seed's weight of faith in his heart, shall not be admitted into the Fire.” No doubt, there is indication in the Quran about Hell Fire being temporary and great scholars who shared their opinion regarding it. In the prophetic ahadith there is proof many would be thrown into the fire temporarily, taken out, and sent to paradise but there is also proof of some who will not be shown mercy. In the end however we can share our opinions based on authentic sources in Islam and let final decisions rest with Allah ﷻ: “But all judgment rests with God, the Exalted, the Great!”
 Riyad as-Saliheen Book 1, Hadith 419
 Al Quran 7:156 – Asad Translation.
 Al Quran 6:28 & Al Quran 11:106-107
 Bukhari, on the authority of Abu Said al-Khudri, in Kitab al-Iman and Kitab Bad al-Khalq; also Muslim, Nasai and Ibn Hanbal - Asad 1980
Heterodox view i.e. not widely accepted by majority scholars.
Who are the Disbelievers? - Yusuf 2008
 Sunan Ibn Majah Vol. 5, Book 37, Hadith 4116
 Jami at-Tirmidhi 1998
 Al Quran 40:12 – Asad Translation.