"Now a certain man was sick, named Lazarus, of Bethany, the town of Mary and her sister Martha.
Therefore his sisters sent unto him, saying, Lord, behold, he whom thou lovest is sick. 
When Jesus heard that, he said, This sickness is not unto death, but for the glory of God, that the Son of God might be glorified thereby."
John 11:1,3,4

We must not misunderstand Jesus' comment of Lazarus' sickness. He was not saying, "Lazarus' sickness isn't unto death; but that his suffering with this sickness to bring God glory."

If we're not careful, we can get confused because we don't study the Word enough to rightly divide it.

Jesus wasn't talking about the problem. He was talking about the result. Jesus always talked about the end result. He was saying the end result of this sickness will not be death but the glory of God. His life was given back to him when Jesus raised him from the dead.

Lazarus' sickness wasn't for the glory of God. It was his resurrection from the dead that brought God glory; the end result.