O you who believe! If you help (in the cause of) Allah, He will help you, and make your foothold firm.
But those who disbelieve (in the Oneness of Allah Islamic Monotheism), for them is destruction, and (Allah) will make their deeds vain.
That is because they hate that which Allah has sent down (this Quran and Islamic laws, etc.), so He has made their deeds fruitless.
Chapter 47 Muĥammad : Verses 7-9
Support Allah’s Cause, He will then support You
Allah then says:
(O you who believe! If you support (the cause of) Allah, He will support you and make your foothold firm.) This is similar to His saying,
(Indeed, Allah will surely support those who support Him (His cause).) (22:40) That is because the reward is comparable to the type of deed that is performed. Thus, Allah says here,
(and make your foothold firm.) Allah then says,
(But as for those who disbelieve — misery awaits them) This misery is the opposite of making firm the footholds of the believers who support the cause of Allah and His Messenger . It has been confirmed in a Hadith that Allah’s Messenger said,
(Misery awaits the servant of the Dinar; misery awaits the servant of the Dirham; misery awaits the servant of velvet. Misery awaits him, and degeneracy; and if he is pricked by a thorn, may he not find anyone to pull it for him.) This means may Allah not cure him. Then Allah says,
(and (Allah) will make their deeds vain.) meaning, He will nullify them and make them fruitless. Thus, Allah says,
(That is because they hate that which Allah has sent down;) which means that they did not want or like what Allah revealed.
(so He made their deeds fruitless.)