Belief in the predestination and the Decree of ALLAH is an article of faith in Islam. We may consider the word Decree as Qadir, one of the names of ALLAH which tells about the authority of the ALLAH. It is said in the Holy Quran as “No doubt, ALLAH is capable of everything”.
According to the teachings of Islam we, the Muslims, consider that everything is done with the order of ALLAH Almighty. whether it is blowing of the wind or it is rain, it is birth of a baby or death of an old age person, all are impossible to happen without the orders of ALLAH Almighty.
The holy Quran explains it in Surah-e-Fatiha as
“All praise is for ALLAH, Lord of the worlds, the Most Gracious and the Most Merciful, the Master of the day of judgment”.
This ayat clearly explains the authority of the ALLAH Almighty that He is the only one who is Lord of the worlds. It is ALLAH Almighty who is Lord of the day of judgment. Whatever the punishment or reward will be given to the people, it is total authority of the ALLAH Almighty because he is the Lord of the world including this world and the other world where we will live our life after death.
In the same way at some other place in the Holy Quran said that “No slumber can seize him nor sleep All things in heaven and earth are His”. This ayat also explains that He is the lord of heaven and He is free from sleep.
All the Muslims believe that everything that has happened in the universe, what is happening in the universe and what will be happened I the universe will be done according to the will of ALLAH.
It is ALLAH who is the only God. In another place, the Holy Quran says
“There is no god but He. The ever-living, the sustainer of all existences”.
Now if someone reads this ayat, he will understand that the ALLAH Almighty is the sustainer of our world and all the things which exist in the whole world or even in the universe.
Now everyone can easily understand the concept that everything belongs to ALLAH almighty but it doesn’t mean that ALLAH didn’t give us the power to think anything. ALLAH gives us power to think and take decisions but all of these powers are according to his will and the laws given by Him. He created the world and allow all the humans to live according to their choices but he will reward those who will act according to the teachings of Islam. So it should also be kept in mind that all of our good deeds will be rewarded in the form of Jannah and all of our bad deeds will lead us towards punishment in the fire.
Whatever will happen at the day of judgment, nobody knows it but one thing is clear that ALLAH Almighty is and will be the only authority on that day. Nobody can challenge His authority today, tomorrow and even on the day of judgment. He is Malik ul Mulk (the king of all the kings).