I was recently pondering on why it took me so long to discover reformed theology, and how my beliefs changed before/after reading reformed theology -- and as I traced my thoughts, it seems like a key point I hit was the doctrine of predestination.
Before believing in predestination, my notion of Christianity was something like: God vs Satan is fighting in some huge battle. I get to play a part. I'm important. I choose who to serve, and I can influence other humans in either direction.
After understanding predestination, it was something like: wow, I'm absolutely useless. There's all these angelic beings worshipping God, God really doesn't need me, and I don't have much influence over whether God or Satan wins, and I don't have much influence even other whether people ultimately get saved.
This realization then somehow paved the door for understanding reformed theology -- i.e. the focus of the Bible is about God, rather than humans.
Thus, is the doctirne of predestination considered a core pillar of reformed theology? Are there any well known doctrines / documents (accepted by reformed theologists) that argue against predestination?