How can we reconcile between the name of Allah al-Aakhir (the Last) and the fact that the people of Paradise will be in Paradise forever and the people of Hell will be in Hell forever
Question

                If we will live forever in Paradise, and there will be no death there, does that not contradict the fact that nothing is eternal except Allah?
Praise be to Allah.
    
    Firstly: 

    
    There is no doubt that when the people of Paradise enter 
    Paradise, they will abide therein and enjoy its pleasures for ever and ever. 
    This is the belief of Ahl as-Sunnah wa’l-Jamaa‘ah, that the people of 
    Paradise will enjoy its pleasures and abide therein for eternity, and the 
    people of Hell will be punished in the Fire and abide therein for eternity. 
    Allah, may He be exalted, says (interpretation of the meaning):

    
    “But those who believe (in the Oneness of Allah — Islamic 
    Monotheism) and do deeds of righteousness, We shall admit them to the 
    Gardens under which rivers flow (i.e. in Paradise) to dwell therein forever. 
    Allah’s Promise is the Truth; and whose words can be truer than those of 
    Allah?”

    
    [an-Nisa’ 4:122]

    
    “Verily, Allaah has cursed the disbelievers, and has prepared 
    for them a flaming Fire (Hell).

    
    Wherein they will abide for ever, and they will find neither 
    a Wali (a protector) nor a helper”

    
    [al-Ahzaab 33:64, 65]. 

    
    Al-Bukhaari (4730) and Muslim (2849) narrated that Abu Sa‘eed 
    al-Khudri (may Allah be pleased with him) said: The Messenger of Allah 
    (blessings and peace of Allah be upon him) said: “Death will be brought in 
    the form of a black and white ram, then a caller will call out: O people of 
    Paradise! They will crane their necks and look, and he will say: Do you 
    recognize this? They will say: Yes; this is death – and all of them will 
    have seen it. Then the call will go out: O people of Hell! They will crane 
    their necks and look, and he will say: Do you recognize this? They will say: 
    Yes; this is death – and all of them will have seen it. Then it will be 
    slaughtered, then it will be said: O people of Paradise, it is eternal and 
    there will be no death. O people of Hell, it is eternal and there will be no 
    death.” Then he recited the words: “And warn them (O Muhammad) of the Day 
    of grief and regrets, when the case has been decided, while (now) they are 
    in a state of carelessness” – those who are in a state of carelessness on 
    the people of this world – “and they believe not” [Maryam 19:39]. 

    
    Thirdly: 

    
    This idea that you mentioned in your question, that “nothing 
    is eternal except Allah” is an idea for which there is no basis in Islam; 
    rather it is a false idea according to the consensus of the Muslims, who are 
    unanimously agreed that the people of Paradise will abide therein forever 
    and ever, and there will be no death, and the same applies to the people of 
    Hell, those disbelievers who are its people. 

    
    Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) 
    said: 

    
    The early generations of this ummah and its imams (leading 
    scholars) are unanimously agreed that among created things there are some 
    that will never cease to be. They are Paradise, Hell, the Throne, and so on. 
    No one suggested that all created things will cease to be except a group of 
    innovators among the People of the Book. This is a false idea. 

    
    End quote from Mukhtasar al-Fataawa al-Masriyyah 
    (1/169). 

    
    Thirdly: 

    
    Here we should point out two things: 

    
    ~1~

    
    that the eternal existence of some created things which Allah 
    has decreed will remain forever in the Hereafter will have been preceded by 
    non-existence. As for Allah, may He be glorified and exalted, He is First, 
    with no beginning, and Last, with no end. 

    
    ~2~

    
    that the eternal existence of created beings is a gift from 
    Allah. Just as the created being only exists because Allah created him, and 
    he did not bring himself into existence on his own or with the help of any 
    other created being, similarly the continued existence of creatures in the 
    Hereafter is a gift from Allah to them, and will only be because of His 
    power of creation and His will and decree. 

    
    This shows us that the continued existence of all creatures 
    and their eternal existence in the Hereafter in no way resembles the eternal 
    existence of the Creator, may He be glorified, and that that which is unique 
    to Allah, may He be exalted, in that regard is not only that He will remain 
    forever and never cease to be; rather the Creator, may He be exalted, is 
    unique in that in a manner that befits Him; He will exist forever in a 
    perfect manner as befits the Creator, and the created being will exist in a 
    manner that befits him as having been created by Allah. 

    
    Shaykh al-Islam (Ibn Taymiyah – may Allah have mercy on him) 
    said: 

    
    We must be certain that there is nothing like unto Allah in 
    His essence, in His attributes or in His actions.

    
    End quote from Majmoo‘ al-Fataawa (13/379) 

    
    Fourthly: 

    
    With regard to His eternal existence, Allah, may He be 
    glorified, possesses an attribute which no one shares with Him, which is the 
    attribute of being the Last. The Prophet (blessings and peace of Allah be 
    upon him) said: “O Allah, You are the First and there is nothing before You; 
    You are the Last and there is nothing after You. You are the Manifest (al-Zaahir) 
    and there is nothing above You; You are the Hidden (al-Baatin) and there is 
    nothing beyond You.” Narrated by Muslim (2713). 

    
    Shaykh al-Islam (Ibn Taymiyah – may Allah have mercy on him) 
    said: So there is nothing before Him, nothing after Him, nothing above Him 
    and nothing beyond Him.

    
    End quote from Majmoo‘ al-Fataawa (16/359). 

    
    He also said: 

    
    He is the First before Whom there is nothing; he is the Last 
    after Whom there is nothing; he is the Ancient of Days, the Eternal, the 
    Everlasting Who will never cease to be.

    
    End quote from Dar’ Ta‘aarud al-‘Aql wa’n-Naql, 1/69 

    
    Ibn al-Qayyim (may Allah have mercy on him) said: 

    
    Allah’s being the First means that He existed before the 
    beginning of all others besides Him, and His being the Last is affirmed and 
    means that He will outlast all others besides Him. His being the First means 
    that He was there before all things and His being the Last means that He 
    will remain after the end of all things. His being the Manifest implies that 
    He is above all things; the meaning of Manifest implies highness and being 
    above, for that which is manifest of anything is that which is above and 
    encompasses what is inside. His being the Hidden means that He is aware of 
    all things, in the sense that He is closer to a thing than itself. This 
    nearness is not the nearness of the lover to his beloved; the two are quite 
    distinct and different. 

    
    What these four names and attributes convey is encompassing 
    and being aware, and that is in two senses: time and place. His being the 
    First and the Last encompasses near and far. Everything that is before 
    something else is within the framework of His being the First, and 
    everything that comes after something else will end within the framework of 
    His being the Last. Thus His being the First and the Last encompasses the 
    early and the late. His being the Manifest and the Hidden encompasses 
    everything that is manifest and everything that is hidden. Nothing is 
    manifest but Allah is above it, and nothing is hidden but Allah is beyond 
    it. Nothing is first but Allah is before it, and nothing is Last but Allah 
    is after it. The First refers to His prior existence from eternity; the Last 
    refers to His everlasting existence; the Manifest refers to His highness and 
    greatness; and the Hidden refers to His closeness and nearness. He preceded 
    all things by being the First, and will remain after all things by being the 
    Last; He is above all things by being the Manifest, and He is nearer than 
    all things by His being the Hidden. No heaven can hide another heaven from 
    Him, no earth can hide another earth from Him; nothing above can hide from 
    Him anything that is below. Rather the hidden for Him is manifest, the 
    unseen for Him is seen, what is far for Him is near, and what is secret for 
    Him is known. These four attributes refer to the pillars of Tawheed. He is 
    the First yet He is the Last, and the Last yet He is the first; He is the 
    Manifest but He is Hidden, and He is the Hidden yet He is the Manifest. He 
    has always been and always will be, Manifest and Hidden.

    
    End quote from Tareeq al-Hijratayn (31). 

    
    And Allah knows best.