Here's an interesting perspective on the conundrum of the free will of man vs God's sovereignty. Let's look at how the Bible was written. The Bible contains the very words of God. 2 Timothy 3:16 says, "All scripture is breathed out by God..." (ESV). Paul is saying that God breathed out his words and the Biblical authors wrote them down. In other words, God is the author of every word of the Bible. Every sentence construction, every phrase, every metaphor; all of them are God's words. He chose to put them down this way.
On the other hand, we recognise that human agents did the actual writing. And we recognise that the 40 Biblical authors were not robots when they penned the words. There are of course, numerous times that God told them to write down specific messages ("Thus says the Lord...") but by and large, we can see the character of the author shine through in his words. John for example, in writing the Gospel of John, used much simpler Greek than Paul did in his letters. And Paul, out of his own volition, sat down to pen a letter to Philemon, asking him to reconcile with his slave Onesimus. In fact, many times Paul writes in his letters, "I, Paul, write this with my own hand..." just to prove that he is the author of the letter.
So which is it? Did men write the Bible with their own wills and personalities, or did God write the Bible? The answer of course is both. Yes, men did write the Bible. Often they chose to write out of their own will. They wrote in their own style, with their favourite vocabulary, using imagery and metaphor that they were familiar with. We can clearly see this as we read the Scripture. Yet, God is the ultimate author of the Bible. Every word comes from him. So even though Paul is writing to Philemon, the words that come out are God's words. This is a profound mystery. The Bible is written by God and also written by men. It is a perfect example of men exercising free will and God have complete sovereignty over his Word. To put it another way, the Bible (God's written Word) is 100% human and 100% divine (Isn't it amazing that Jesus, whom we call the living Word, is also 100% human and 100% divine?)
Now, there are those (like the Arminianists) who say that man has complete free will, which therefore means that God doesn't know ahead of time what we will choose but instead reacts to our choices. What are they to say about the human and divine nature of the Bible? If men had complete freedom to express themselves, does it mean that the Bible is not 100% breathed out by God? Or if they accept that the Bible is 100% breathed out by God, then why are there such varied tones and styles in the Bible? We can clearly see how each Biblical author writes differently from another.
A metaphor for this is like having two camps of people arguing about two different photos of the same object. The first camp argues that with the photo they have, the object is clearly a circle. The second camp argues that with the photo they have, the object is without a doubt a rectangle. And the two camps can't never get to a consensus as to whether the object is a circle or a reatangle. They finally turn to the creator of the object and ask him what shape it really is. And the creator says, "Yup." He pulls out the object. In three dimensions, it turns out to be a soda can. When view from its end, it does indeed look like a circle. And when viewed on its side, it is a rectangle. The object is both shapes at the same time; in fact it is more than both shapes combined. The two camps could not see this with their two-dimensional photos.
Such is free will and God's sovereignty. Is God sovereign? Yes, he is. Do men have free will? Yes, they do. Is this a profound truth and mystery? Yes and yes. One only needs to look at the Bible to see this interplay of man's free will and God's sovereignty living together in harmony. The truth is larger than what we understand, we two-dimensional creatures who have trouble comprehending a 3D God.

