We need to have free will so that we can choose to either follow God or disobey and walk away in sin. Theists have to insist that we have free will to support the argument we need God's help to be saved through the sacrifice of his son. If we didn't have a choice then we don't need to be saved by Jesus. It all would be on God not us as he would be the only one in control to alter any outcome. No free will equals no need for salvation which is why they argue so hard for it. Atheists argue if the game is played the way they say and God knows all outcomes then there isn't free will anyway. The game is played only for God's grotesque enjoyment of his weak minded creations. Theists never seem to get that part at all. Omniscience and omnipotence means he knows it all and can change it. If you can make the rules and know the outcome the game is rigged and you can't win. This means you can't remove free will from man and have theism especially Christianity as anything meaningful. It wouldn't be.