"But to summarize Walls’ excellent exposition of the core problem with Calvinism is that if God could have determined that all men freely worship Him, and praise Him, and He chose not to, but He could have, then He did not do so because He did not WANT to do so in contrast to those He DID want to save irresistibly. Since Calvinists admit that God does whatever He wishes or desires, then it follows that all things that God determined are based upon what He desired and wanted to determine. If God then determined that others be eternally damned, then God predetermined men to be damned simply because He WANTED TO in order to get glory for Himself and prove His sovereignty. Yet who God had to prove it to is a mystery because the necessity that God needed to prove His sovereignty implies that God was somehow not content before He created anything and became sovereign over what He created. It wasn’t enough that the Father loved the Son throughout eternity, God needed and therefore depends on evil in order to vindicate Him (from who?) and thus not only is this a gross caricature of the nature and character of God, but a distortion of God’s love."'
Taken from godisopen.