One of the strangest arguments against the existence of free will (which is, in itself, a strange thing to be using your free will to argue) is that if we have free will, that in some way diminishes God's sovereignty because it means there are limits to God's power. If free will does not exist, God retains full control of anything and everything, but if it does exist, there are beings that are, at least in some sense, more powerful than He is.
There are many problems with this argumentation, but for this article, let's focus only on one: The contradiction it causes. In effect, while it denies that such beings exist, it still suggests (erroneously) that beings with free will would be greater than God, and therefore God is not free to create free beings. In other words, if you believe free will means God is not sovereign, you're still saying there's something God can't do. The difference is, you're on the "God can tempt us to sin" side, and I'm on the James 1:13 side.
In James 1:13, we are told that God does not tempt anyone to sin, but rather, verse 14 continues to tell us we are tempted when we are drawn away by our own desires. In other words, our will contradicts God's will, which causes us to disobey God. Free will simply must exist, otherwise whence commeth sin? At least one thing must exist with its own desires separate to God's, otherwise sin could not exist; everything would be perfect already. Given that each of us is held responsible for our own sin, and of course I just showed you where scripture says we are drawn away by our own desires, it is necessary to conclude that we all have free will.
According to His sovereign will, God has chosen to give mankind free will. It is not unlimited, we cannot disobey Him without His consent, but the fact that He gives consent is evident by the fact that He does not restrain us completely. Only one man has ever walked the Earth in complete observance to the will of God. The rest of us have gone our own way, which is why we require salvation. Thank God that He offers that gift to us so freely.