"Why does He still find fault?"

In Romans 9 Paul walks through the standard objections of God's choice of who He will save. The first objection is "Is it fair?" (Rom 9:14) Paul assures his readers that there is no injustice with God. Salvation is based on His mercy and His selection alone (Rom 9:16) The second objection is "Why does He still find fault?" (Rom 9:19) If God is sovereign and God chooses whom to save and God saves them, how can He find fault with anyone? That is, if God is Sovereign, can Man be held culpable?

There is an interesting passage in Isaiah that might address this question. (Paul doesn't. "Who are you, oh man, to answer back to God?" (Rom 9:20).)

Woe to Assyria, the rod of My anger
And the staff in whose hands is My indignation. (Isa 10:5)

What's going on here? It is God speaking. He is pronouncing "woe", the ancient Hebrew curse. He is pronouncing this curse upon Assyria, an idolatrous nation. What else do we know about Assyria? They are "the staff in whose hands is My indignation." Okay, now, hold on. This is a curse on an idolatrous nation who God is using to punish Israel. Huh? God is sending them and commissioning them (Isa 10:6) and they are doing it and He is pronouncing a curse on them. How is that possible? They're going to do what God intends them to do and He is cursing them for it? Why?

Yet it does not so intend,
Nor does it plan so in its heart,
But rather it is its purpose to destroy
And to cut off many nations. (Isa 10:7)

Oh, now that's interesting. So Assyria is assigned by God to punish Israel for her idolatry, but Assyria is not doing it because God has assigned them to do it. They are doing it for their own bad reasons. And that is why God is pronouncing this woe upon them.

It's an interesting juxtaposition of Man's free will and God's Sovereignty. It is a clear case of God's overarching rule and Man's responsibility for his own actions. Like Judas Iscariot, predestined to betray Christ and with a woe pronounced against him for it (Luke 22:22), Assyria was God's chosen tool that opted for personal gain to attack God's people. God permitted, even ordained it because God's people needed correction, but Assyria isn't free of culpability for it because of their sinful motivation. Regardless of where you stand, the Bible is clear that God is regarded as absolutely Sovereign and Man is culpable for his sinful choices.