Looking at it, it seems to me that fate of overall mankind is predetermined, or calculated, not of individuals. Individuals posses their own level of intelligence, reasoning as well as desires etc and they have the free will choose between two of the available paths, either they choose the path which lead to their personal satisfaction in this world or they choose a path which takes them to Allah. As about supplication and prayers, religion urges upon them just so that individuals get some respite and peace from the desires triggered in their soul, in other words prayers are just to enforce patience. Fulfillment of a desire is, perhaps, almost always a result of one's personal efforts and calculations based upon his/her level of intelligence and assessment which is why sometimes we have prayers answered and sometimes we don't, however pursuit of desires has a potential of leading an individual away from Allah and on a path of greed and selfishness therefore religion proscribes against it and advices people to leave matters to Allah.

It may sound deistic, but Allah (SWT) knows best . I think Allah (SWT) is much bigger than a being who is intervening in everyday life of individual human beings who often bring themselves in messy situations . Or maybe Allah does intervene on occasions, only when someone following His path is annoyed. But certainly all the people praying for marriage, jobs, happy life etc are not getting their prayers answered, this is a factual observation .

For example we have a policeman. Before leaving for duty he prays to Allah O God, my kid needs something, please make arrangement for that. While on duty someone offers him a bribe and he happily takes it and is thankful to God . This is human nature. Human beings have empathy for others as well as lust for their own desires. Allah made calculations based upon this very human nature and determined the final destiny of mankind.

On the other hand we have another policeman. Just like the previous one he does the same pray and leaves for duty. While on his path he finds some money, he takes it and is thankful to Allah, however soon he finds someone looking for the same money and he returns it. Then someone offers him a bribe but he refuses to take it. In the end his desire is not fulfilled and he has an angry kid at home . However he remains calm and stick to his faith. With this attitude, gradually this policeman will start earning the trust of other people and become strong, however his newly earned power is again a test of how he uses it. Life is a continuous test of patience and pursuit of lust. Allah knows very well that very few people are capable of surviving this test while keeping their faith intact, vast majority of people have very basic faith and often fall pray of desires. Therefore Allah has determined the fate of mankind, which is commonly known as destiny . On earth everyone is rewarded by the system.

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The precondition for existence of a higher humanity is not the state, but the nation possessing the necessary ability.