Richard Watson's article on Omniscience (a part of his systematic theology) discusses God's knowledge and foreknowledge. Watson starts out by providing the scriptural passages indicating that God's knowledge is infinite. He then provides arguments from reason supporting God's infinite knowledge; namely, from God's being the First Cause, from His wisdom displayed in His works and finally from Greek philosophers who conclude God is omniscient based on the light of nature and express themselves well, so long as they expressed themselves generally, on
Next Watson takes on the idea that God does not know our future choices; either because He doesn't choose to or because such foreknowledge implies a contradiction. Watson destroys this idea with scripture on prophecies of future choices and demonstrates what damage this does to God's providence.
Then Watson reconciles God's foreknowledge with human freedom by pointing out the difference between certainty and necessity (i.e. that a thing will happen vs. it must happen). Watson points out that knowledge is not the cause of a thing known, so if something is making that thing necessary, it's not God's knowledge.
One of the ways people have attempted to reconcile God's foreknowledge with human freedom is to deny that God's foreknowledge and our knowledge are similar in nature. Watson does not like this approach. While God's knowledge is infinite and ours is finite; the nature of the knowledge is the same. Likewise, God's goodness is infinite and He is an infinite Spirit and our goodness and spirit are finite, yet they have the same nature. Finally, Watson denies that God is impassive, while maintaining God's immutability, by removing from His emotions all the imperfections that are attached and commingled with our emotions.
Watson wraps up the discussion of God's foreknowledge by noting: the question is not, how to reconcile God's prescience with the freedom of man; but how to reconcile the conduct of God toward man, considered as a free agent, with his own prescience; how to assign a congruity
to warnings, exhortations, and other means adopted to prevent destruction as to individuals, with the certain foresight of that terrible result. But Watson insists that in permitting sin, no moral attribute of God is impugned.
In an interesting footnote discussion of middle knowledge, Watson quotes Curcellaeus who states Gomarus (Arminius' opponent) used middle knowledge with respect to the fall (and only the fall), to avoid the idea that God is the author of sin.