What is meant by amaanah in the verse “Truly, We did offer al-amaanah (the trust) to the heavens and the earth, and the mountains”?
Question

                What is the amaanah (trust) that Allah, may He be glorified and exalted, “offered to the heavens and the earth but they declined to bear it and were afraid of it, but man bore it; verily he was unjust (to himself) and ignorant (of its results)”?
Praise be to Allah.
      Allah, may He be 
      exalted, offered obedience to Him and His obligations and limits to the 
      heavens and the earth and the mountains in such a way that if they did 
      well they would be rewarded, but if they neglected their duties they would 
      be punished. They refused to bear it out of fear that they might not do 
      what was enjoined upon them, but man took it on, and verily he was unjust 
      (to himself) and ignorant (of its results). 

    This is the 
    explanation of the verse in which Allah, may He be glorified and exalted, 
    says: “Truly, We did offer al-amaanah (the trust or moral responsibility 
    or honesty and all the duties which Allah has ordained) to the heavens and 
    the earth, and the mountains, but they declined to bear it and were afraid 
    of it (i.e. afraid of Allah’s torment). But man bore it. Verily, he was 
    unjust (to himself) and ignorant (of its results) [al-Ahzaab 33:72]”. 

    The interpretation 
    of the amaanah (trust) as referring to shar‘i duties is the view of Ibn 
    ‘Abbaas, al-Hasan al-Basri, Mujaahid, Sa‘eed ibn Jubayr, ad-Dahhaak ibn 
    Muzaahim, Ibn Zayd and most of the commentators. 

    See: Tafseer 
    at-Tabari, 20/336-340; Tafseer Ibn Katheer, 6/488-489; 
    al-Jaami‘ li Ahkaam al-Qur’an, 14/252-253; Fath al-Qadeer, 
    4/437. 

    Qataadah said: The 
    amaanah (trust) is the religion, obligatory duties and limits set by Allah. 

    It was also said 
    that what is meant by the amaanah here is whatever people entrust one with. 

    Some of them said 
    that it refers to ghusl in the case of janaabah. 

    Zayd ibn Aslam 
    said: The amaanah is three things: prayer, fasting and ghusl in the case of 
    janaabah. 

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

    There is no 
    contradiction between these opinions; rather they are all in harmony and 
    refer to responsibility and accepting the commands and prohibitions on the 
    basis of their condition, which is that if they do well they will be 
    rewarded and if they neglect them they will be punished. Man accepted this 
    amaanah despite his weakness, ignorance and injustice (to himself), except 
    those who Allah guides. End quote. 

    Tafseer Ibn 
    Katheer, 
    6/489 

    At-Tabari (may 
    Allah have mercy on him) said:  

    The most correct 
    of these opinions is that of those who said that what is meant by the 
    amaanah (trust) here is everything with which one is entrusted with regard 
    to religious commitment and things entrusted to one by people. That is 
    because Allah did not specify any particular type of trust when He said, “Truly, 
    We did offer al-amaanah (the trust)”. End quote. 

    Tafseer 
    at-Tabari, 
    20/342 

    Al-Qurtubi (may 
    Allah have mercy on him) said: 

    The word amaanah 
    is general in meaning and encompasses all the duties of Islam, according to 
    the correct opinion. This is the view of the majority. End quote. 

    Al-Jaami‘ li 
    Ahkaam al-Qur’an, 
    14/252 

    As-Sa‘di (may 
    Allah have mercy on him) said: 

    Everything that 
    Allah has enjoined upon His slave is an amaanah (trust), and the slave must 
    carry them out in the fullest sense. That also includes things that are 
    entrusted to one by people, such as wealth, secrets and the like. The 
    individual must pay attention to both matters and fulfil both trusts. 
    “Verily! Allah commands that you should render back the 
    trusts to those, to whom they are due” [an-Nisa’ 
    4:58]. 
    End quote. 

    Tafseer 
    as-Sa‘di, 
    p. 547 

    Ash-Shanqeeti (may 
    Allah have mercy on him) said: 

    In this verse 
    Allah, may He be glorified and exalted, tells us that He offered the 
    amaanah, which is the taking on of duties and the consequences of reward or 
    punishment, to the heavens and the earth and the mountains, but they refused 
    to bear it and were afraid of it. In other words, they were scared of the 
    consequences of taking on this trust, lest that lead to the punishment and 
    wrath of Allah. This offer, refusal and fear happened in a true sense. Allah 
    created the heavens and the earth and the mountains with a sense of 
    understanding, the nature of which only Allah knows and we do not know. Thus 
    they understood when this trust was offered to them, and they refused and 
    were afraid. End quote. 

    Adwa’ al-Bayaan, 
    36/139 

    To sum up: 

    The amaanah 
    (trust) mentioned in this verse, that Allah offered to the heavens and the 
    earth and the mountains, but they refused to bear it and were afraid of it, 
    but man took it on, is the Islamic duties, whether that has to do with 
    duties towards Allah, may He be exalted, or duties towards His slaves. The 
    one who fulfils his duty towards Allah and towards His slaves will be 
    rewarded, but the one who neglects his duty towards Allah and towards His 
    slaves deserves punishment. 

    And Allah knows 
    best.