We Muslims firmly believe that Almighty Allaah answers our prayers sooner or later. Inspite of a wife's consistent, firm, prayer (ever since she got married to him) for the prolonged life of her spouse, how the sudden death of a person could be explained in this context. In an Islamic sense, does it mean that inspite of our prayers, destiny precedes prayer? If so, prayers are just formalities for things pre defined by destiny. Please clarify my doubts and correct me if I have misunderstood the concept.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

First of all, it should be mentioned that there are conditions for a supplication to be accepted, among which are the following:

A) Sincerity: Allaah Says (what means): {So invoke Allaah, [being] sincere to Him in religion.}[Quran 40:14]

B) The supplication should not be about severing ties with kinship or about a sin, as the Prophet said: "There is no Muslim who supplicates Allaah without supplicating for a sin or severing ties with kinfolks except that Allaah grants him one of the three following: to immediately respond to his supplication, or to save it for him for the Hereafter (i.e. add to his reward instead), or to protect him from a misfortune equal to his supplication." The Companions then said: "In such a case, we will supplicate as much as we can."  The Prophet remarked: "Allaah gives abundantly [His treasures never end]."

C) The provision and clothing of the person who supplicates should be from lawful sources. The Prophet mentioned (the case of) a man who is in constant travel for long distances, being always unkempt and dusty, and who raises his hands towards the heavens and supplicates saying: "O Lord! O Lord! While his food and drink are from ill-gotten money, his clothing is from ill-gotten money and he is fed with what is forbidden; so how can his prayers be answered?" [Muslim]

D-The person who supplicates should not hasten the result of his supplication, as the Prophet said: "Your supplication is answered as long as one does not say "I supplicated but it was not responded to." [Al-Bukhari]

In addition to this, if Allaah does not give to the person exactly what he asked for, this does not mean that his supplication is not answered, as mentioned in the above narration that Allaah gives him one of three things.

Ibn Hajar said: "The way the supplication is answered differs, sometimes what the person exactly asks for happens immediately, sometimes it happens but with a delay for wisdom, and sometimes one's supplication is answered by something that does not give a prompt benefit, but in reality it is a prompt benefit or better than a prompt benefit."

Therefore, you should know that the death of her husband does not mean that her every supplication is not answered. It might be that Allaah answered her supplication and extended the age of her husband to the age beyond which there is no extension.

As regards whether Allaah's Decree comes before the supplication, the answer is that the supplication is included in Allaah's Decree. Allaah Decrees things according to His Knowledge and Might, as He predestined, for instance eating one's full [after eating] and being cured by taking medicines. So it is not correct to say that supplications are only formalities and should be ignored as everything is predestined. Can one say that we should stop eating because Allaah predestined eating one's fill, and we should abandon medicines because the cure is something predestined? The answer is, 'No'! In the same way, one should not abandon supplications on the pretext that predestination comes first. The supplication is also predestined and there is no contradiction between the supplication and Predestination. The Prophet used to supplicate continuously. For instance, he supplicated Allaah to guide some people, as he said: "O Allaah! Guide the tribe of Daws and bring them to me (as Muslims)." [Al-Bukhari and Muslim] So he supplicated despite the fact that their guidance is predestined and it does not depend on a person. However, Allaah predestined their guidance by predestining the supplication of the Prophet, (for them). The Prophet also supplicated for Anas Ibn Maalik and said: "O Allaah! Multiply his wealth and his progeny, and bless him in what You have given him." [Al-Bukhari and Muslim] It is known that the provision of Anas is something that is predestined. However, Allaah predestined the occurrence of this provision upon the supplication of the Prophet . Allaah Says (what means): {Indeed, We have created all things with predestination.} [Quran 54:49]

Allaah Knows best.