We Muslims are told that our fate has been pre-written. If this is so, then why will some people be sent to Hell for deeds which were written down beforehand and they could do nothing about them? Also, what is the purpose of Du’ā when it cannot change pre-determined fates?

I will allude to certain points which I think may prove a little helpful in removing the confusion which in general seems to surround the concept of predestination:

a) The Almighty has given us the free will to select between good and evil. If a person intends to adopt the right path, it is up to him, and if he intends to adopt the wrong path, it is entirely his choice. It is after this liberty given to us in exercising our intention that the Almighty will reward or punish us. This retribution therefore will be based on our own deeds and not under any compulsion of fate.

b) Whatever is written down about our fate, concerns Allah's knowledge about our fate. His prior knowledge does not mean that we are under any compulsion to do what has been written down. It only means that He knows what we are going to do. Consequently, if Allah knows beforehand that such and such people will go to Hell or certain others will go to heaven, then it only means that such people will do the deeds which will lead them to a bad fate. In other words, a person's deeds will determine his fate only. However, whatever deeds he will do are already in the knowledge of Allah.

c) Du‘ā has a great significance since it is an expression of Tawhīd. There are things which will be given to us if we only ask for them; otherwise we will not receive them. In other words, they are dependent upon Du‘ā. So one cannot and should not disregard it.