The ahaadeeth about the Mahdi and the descent of the Messiah (peace be upon him) are no excuse not to strive and do good deeds
Question

                Some people understand from the ahaadeeth about the Mahdi and the descent of the Messiah ‘Eesa ibn Maryam (Jesus the son of Mary, peace be upon him) that these are an excuse not to strive for Islam, so they should sit and wait until the Mahdi appears or the Messiah descends for the glory of Islam and the Muslims to be restored. What is your opinion on this understanding?.
Praise be to Allah.
    This miserable state that the Muslim ummah is in nowadays is 
    very shameful. All the Muslims are responsible for setting things straight, 
    but some Muslims fail to strive, relying on their hopes and avoiding 
    correcting the sorry state of the ummah on the grounds that this was caused 
    by those who came before us and will be set right by those who come after 
    us. So they do not strive to support the religion of Allaah, on the grounds 
    that the Mahdi is the one who will do that. 

    This is escaping into hopes whilst failing to put into effect 
    the means prescribed in sharee’ah. Allaah says (interpretation of the 
    meaning): 

    “It will not be in accordance with your desires (Muslims), 
    nor those of the people of the Scripture (Jews and Christians), whosoever 
    works evil, will have the recompense thereof, and he will not find any 
    protector or helper besides Allaah”

    [al-Nisa’ 4:123]
This negativity which 
    some of the Muslims are suffering from nowadays can have no basis in the 
    texts of sharee’ah; rather it is due to misunderstanding, helplessness and 
    laziness, and evasion of responsibility. 

    Allaah has commanded the Muslims to strive and work for this 
    religion, to call people to Allaah, to debate with the kuffaar and call them 
    with wisdom and beautiful preaching, and to fight them until there will no 
    longer be any shirk on earth. Allaah says (interpretation of the 
    meaning): 

    “And fight them until there is no more Fitnah (disbelief 
    and polytheism, i.e. worshipping others besides Allaah), and the religion 
    (worship) will all be for Allaah Alone [in the whole of the world]. But if 
    they cease (worshipping others besides Allaah), then certainly, Allaah is 
    All-Seer of what they do”

    [al-Anfaal 8:39]

    Ibn Katheer (may Allaah have mercy on him) said: 

    Here Allaah commands us to fight the kuffaar until there is 
    no more fitnah i.e. shirk, and the religion (worship) is all for Allaah, 
    i.e., until the religion of Allaah prevails over all other religions. 

    This command does not apply only to some times and not 
    others, rather the Muslims of all times and places are commanded to do 
    this. 

    Undoubtedly working for Islam and to establish it on earth 
    requires the Muslims to strive hard and pursue the means that lead to that. 

    Some people misunderstand the ahaadeeth that have been 
    narrated about the emergence of the Mahdi and the descent of the Messiah 
    ‘Eesa ibn Maryam (peace be upon him), so they are passive and do not strive, 
    and they sit and wait for the Mahdi to appear or the Messiah to come down, 
    and they do not call people to Allaah or strive to make the word of Allaah 
    supreme. But Allaah and His Messenger  (peace and blessings of Allaah be 
    upon him) have commanded us to take the appropriate means and strive hard on 
    earth. 

    Allaah says (interpretation of the meaning): 
“O you who believe! Take 
    your precautions, and either go forth (on an expedition) in parties, or go 
    forth all together”

    [al-Nisa’ 4:71]

    “And make ready against them all you can of power, 
    including steeds of war (tanks, planes, missiles, artillery) to threaten the 
    enemy of Allaah and your enemy”
    [al-Anfaal 8:60]

    “He it is Who has made the earth subservient to you (i.e. 
    easy for you to walk, to live and to do agriculture on it); so walk in the 
    path thereof and eat of His provision. And to Him will be the Resurrection”

    [al-Mulk 67:15] 

    “and for this let (all) those strive who want to strive”

    [al-Mutaffifeen 83:26] 

    “For the like of this let the workers work”

    [al-Saaffaat 37:61] 

    “And whoever desires the Hereafter and strives for it, 
    with the necessary effort due for it (i.e. does righteous deeds of Allaah’s 
    obedience) while he is a believer (in the Oneness of Allaah 
     
    Islamic Monotheism) — then such are the ones whose striving shall be 
    appreciated, (thanked and rewarded by Allaah)”
    [al-Isra’ 17:19] 

    “And take a provision (with you) for the journey, but the 
    best provision is At-Taqwa (piety, righteousness)”

    [al-Baqarah 2:197]

    Allaah commanded Maryam to take the appropriate means when 
    she was at her weakest, as He said (interpretation of the meaning): 

    “And shake the trunk of date palm towards you, it will let 
    fall fresh ripe dates upon you”

    [Maryam 19:25]

    The Messenger of Allaah  (peace and blessings of Allaah 
    be upon him) used to prepare for everything and draw up plans, as happened 
    during the Hijrah (migration to Madeenah). He prepared the mounts and a 
    guide, and he chose a travelling companion, and chose a place to hide until 
    the search for him had died down, and he protected all of that with secrecy. 
    This is how he conducted himself in all his battles and military campaigns, 
    and this is how he trained his companions. They used to meet their enemies 
    equipped with all kinds of weapons. The Messenger of Allaah  (peace and 
    blessings of Allaah be upon him) entered Makkah (at the conquest) with a 
    helmet on his head, even though Allaah said (interpretation of the 
    meaning): 
“Allaah will protect you from mankind”

    [al-Maa’idah 5:67]

    When he traveled for jihad or Hajj or ‘Umrah, he took his 
    provisions and more with him. 

    The Prophet  (peace and blessings of Allaah be upon him) 
    said: “Strive for that which will benefit you and seek the help of Allaah, 
    and do not feel helpless.” Narrated by Muslim, 2664. 

    We can imagine the state in which the call and the ummah 
    would have ended up if the previous generations had responded to the calls 
    to give up until the Mahdi comes. Would they have been able to defeat the 
    Tatars and Crusaders, and conquer Constantinople?  

    This mistaken understanding of the shar’i texts that have 
    been narrated concerning the Mahdi and the Messiah (peace be upon him) has 
    been criticized by many scholars, daa’iyahs and writers. 

    Shaykh al-Albaani (may Allaah have mercy on him) said: 

    It is not permissible for the Muslims to give up working for 
    Islam and for the establishment of the Islamic state on earth because they 
    are waiting for the Mahdi and the descent of ‘Eesa (peace be upon them 
    both), because they feel despair or they think that it is not possible to 
    achieve any such thing before they come. This is a false and desperate 
    notion. Neither Allaah nor His Messenger  (peace and blessings of Allaah 
    be upon him) told us that Islam will not regain power on earth before their 
    time. It is possible that that may be achieved before then if the Muslims 
    avail themselves of the means that lead to that, because Allaah says 
    (interpretation of the meaning): 

    “If you help (in the cause of) Allaah, He will help you, 
    and make your foothold firm”

    [Muhammad 47:7] 

    “Verily, Allaah will help those who help His (Cause)”

    [al-Hajj 22:40]

    We have to believe in the ahaadeeth which speak of the 
    descent of Eesa (peace be upon him) etc, and reject the false notions of 
    those who say that we should not work and strive and prepare to do that 
    which must be done at all times and in all places. End quote. 

    Professor ‘Abd al-‘Azeez Mustafa said: 

    Jihaad against the kuffaar, no matter who they are, where 
    they are or in what time they exist is obligatory according to sharee’ah; 
    this ruling has not been abrogated. This is an established truth of Islam. 
    This jihad is obligatory when its conditions are met and the relevant 
    rulings apply. It is not one of these conditions or rulings that jihad 
    should be delayed until what is promised comes to pass. This is not the way 
    in which the first Muslims understood it and how they acted. Indeed, when 
    they were told that Allaah would destroy the power of Chosroes with their 
    swords they did not stay in their houses waiting for the news to come true 
    and for that event to happen without any effort on their part. No, rather 
    they prepared themselves for that and made themselves ready until victory 
    came and thus the promise coincided with the decree of Allaah. But some of 
    the Muslims nowadays say no: jihad against the Jews must wait until the 
    Dajjaal appears. Perhaps this is part of the trial (fitnah) of the Dajjaal 
    in this world. 

    This negative talk has affected some of the Muslim youth, so 
    they do not feel any kind of responsibility towards al-Masjid al-Aqsa, the 
    environs of which Allaah has blessed. It has even led many of them to 
    believe more foolish ideas, namely that the Islamic state and the caliphate 
    will not be established until the Mahdi comes. 
I wonder about those who 
    propagate such ideas. It is as if they are saying to the Jews: Be harsh 
    towards your enemies… and to the Christians: Carry on with your aggression… 
    and to the Muslims: carry on being fragmented and disputing and being 
    useless until the Mahdi comes to you. I do not know on what their argument 
    is based, or how they imagine that the Mahdi will come to people who are 
    doing nothing or will support people who are apathetic. End quote.

     See: Al-Mahdi wa Fiqh Ashraat al-Saa’ah by Shaykh 
    Muhammad ibn Ismaa’eel, p. 710-722. 

    We ask Allaah to bring the Muslims back to their religion. 

    And Allaah knows best.