"Why does God allow evil and pain?"
If you read Genesis we can agree that God's original plan was not death or suffering or pain. He created everything good and there were no health problems. So God's plan was not health problems.
So why is there pain in the world then?
For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord. ~ Romans 6:23
Our sin, the breaking of God's law, has caused consequences, pain and suffering and death.
"now it seems like it is his will for evil to exist..."
Let me ask you a question, when Satan sinned in heaven, and let's say God just destroyed him right there, what would have happened? Certainly the other angels might have thought that Satan was right! That God was holding something back from them. Also the motivating factor to serve God would turn to be fear of destruction, rather than selfless love. God allows evil in the world so that we can have time to repent. He also does it to demonstrate that His way is correct and that Satan is a liar and evil. God will wipe sin and evil from the universe... when He returns again.
May I recommend the following DVD which talks about why God allows suffering in the world...
It is often the case that our illness and pain can be the motivating factor for us to seek Him and be saved. As is the case of Naaman in 2 Kings 5. Also trials keep us humble.
Lastly, know that God always heals his people, either today, in the near future, or at the resurrection day.
So there are many reasons why God does so. Sometimes we might not understand all the reasons at this time but we can never question God's love because He proved it at the cross.
May I recommend a site to help...
The LORD is righteous in all His ways,
Gracious in all His works. ~ Psalm 145:17
May the Lord bless you in 2010 if you seek Him!
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