The story of King David comes to mind... He started out as a humble follower of God and His ways and stood up against evil and oppression against the people of God. God used David in a big way to restore God's hope and freedom to His people.
Later in life though, when King David was rich and powerful he decided that he was in control and didn't need God's wisdom, God's protection, or God's ways and chose to take the wife of another man - a faithful soldier in David's army - sleep with her, get her pregnant then plan and execute the murder of her husband to cover his tracks.
The end result was that the child born from that night of lust was cursed to die by David's own doing and very poor choices. This scarred and weakened David for the rest of his life and effected all of his decisions going forward. David was truly repentant and was completely forgiven by God but the damage was done and could not be reversed.
The example here is that when we decide we don't need God and "take control" of our lives it inevitablely ends in disaster.
Let God be God, because we don't fit the role well at all.
I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing.
John 15:5 ESV