If God is omniscient, omnipotent and benevolent, then he knows all, past, present and future, can do all (that does not contradict with his being), and loves all.
If God knows, then, what we will do, before we do it, even before he creates us, then not only do we not have free will, but he is creating the very evil that theists claim we as humans create. In this case he is either not benevolent (not all loving) as he does not stop evil, or not omnipotent, if he cannot. The fact that god is claimed to be the pure source of good would mean that creating evil would be against his being, meaning that he could not create us. In short, there cannot be an omniscient, benevolent, omnipotent entity, meaning that God cannot be infinite as Christians claim, meaning that there can be something greater (according to St Thomas Aquinas himself). This infinite cycle of another being means that God cannot exist.
It makes more sense for there not to be a God, and that the universe came of random chance. Furthermore, Christians believe that God is:
• Fully invested in each of the Father, The Son, and The Holy Sprit simultaneously,
• That he is omniscient, omnipotent, benevolent (whilst always threatening eternal hell) and
• Simultaneously transcendent and playing an active role in the universe.
Need I say more?