SO god knows all and you are going against his plan by making him change it?
My brother, you have completely misunderstood what I said. I'll try and break it down:
Let's say there's a person (X). He gets cancer. Either it can be decreed that he recovers or he doesn't right. Let's say if he wasn't going to pray, it would've been decreed that he dies from it, and if he did choose to pray he was going to recover from it. The person has free will to do what he chooses. But God knows what he will choose, and therefore before He even created anything He'd already decided what to decree for him based upon what the individual was going to do (pray or not pray).
So we're not going against His plan, rather the prayer is encompassed within His plan. If you mean by "change it" that God changed what would've originally BEEN decreed, then yes, in such a sense you could say we have changed something, but not God's plan, because God's plan is what is actually decreed and that takes account of prayer. And in reality to call it a "change" is incorrect, because that would imply that the plan went from one thing to another, which it didn't, the plan was the same all the way through, it's just that it WOULD have been different(not WAS different) if the person didn't pray.
Or god knows all and wants you to beg?
Yes, we believe that God responds to those who pray to Him/ beg to Him, that's the whole point of prayer. We believe that God responds to those who pray, because they have humbled themselves to Him, and He doesn't respond to those who don't pray due to their arrogance by saying that they don't need Him or woteva. Would you respond to such a person? You give someone life, sustenance everything, and then they turn around and say I don't need you anymore, get lost, would you help such a person? And the proof from the Qur'aan for this is:
"And your Lord has said supplicate to me, I will respond to you. Indeed those who are ARROGANT of my worship will enter Hell in HUMILIATION."
(i.e. those who don't pray due to arrogance-most atheists say we shouldn't beg/pray to God even if He exists, out of their arrogance. P.s. I'm NOT saying you're one of them)
Or god knows all and only answers petty wishes and refuses to help the hungry, the poor, war etc.. but he will happily help someone that has cancer well maybe not glady only by chance and only along the same chance of it happening naturally?
There is a hadeeth (narration from the Prophet Muhammad (saw)) which states that all of mankind was seen from the first of them to the last of them (some were blind, some were deaf etc) and somebody asked God "Why did you not make them all the same?" And God responded "I like to be shown Gratitude". Meaning that the reason why bad things happen to us, is to see whether or not we thank God for the good things, it's part of our test.
Secondly, we believe that on the day of judgement everybody will get what they deserve,as God said in the Qur'aan "There is no oppression on this day", meaning everyone will get what they deserve. So if somebody is poor, that will be taken into account, and the person will not be expected to have done as much as others. And If they were poor and Islaam never came to them, then even less is expected. And what matters is the day of judgement, this life is only short. There's loads of issues connected with this, why is there so much suffering in the world, but I think we're diagressing from the main topic of prayer, we could discuss this in another thread later if you want.
Regarding the second part, that He'll help people not gladly but according to the laws of natural probability, I find it amazing that you say such a thing because there's so many incidents where people are cured despite the chances being extremely low, the laws of probability are actually against them in such an instance. How would you explain that? Are you just going to reject that it takes place, even though there's so many reports?
PS what's your position on fate/free will?
Peace