This is one of those areas where Christian logic trips over itself.
My all-powerful, all-knowing God has a Plan. The Plan is based on his infinite wisdom.
But if I beg hard enough, or if enough people beg, he will change that plan.
Can you spot the obvious gaping hole in your logic?
Measuring the Power of Prayer
Christians will trot out their anecdotes of when prayer achieved something wonderful, but of course have forgotten all the times they prayed for something but didn't get it.
But it is quite easy to measure the effectiveness of prayer.
For the first 1800 years A.D. prayer was your only hope when you got sick, got hurt, or were having a difficult childbirth. For the last 200 years other options have become available, like Science. Specifically sanitation, soap, anaesthetics, antibiotics, vaccinations. So which was more effective?
Well Jesus was your only hope, you were pretty well stuffed if you were injured or sick. Life expectancy in 1800 Britain was 40, the same as it had been for centuries. A third of children died before they reached 5. And a fifth of pregnancies ended with the death of the mother.
Now life expectancy in Western world (unless you are very poor) is nearly 80. 7 children in 1000 die before age 5. Maternity deaths are virtually nil - actual figure in US is 13 deaths per 100,000 live births.
Title
Simple and obvious lesson: prayer ain't gonna save you. You'd think it was obvious, but every year we hear of religious nuts who let their children die because they prefer prayer to science. Darwin Awards all round, but the nutjobs never absorb the lesson.