I agree. Without God, all we have is our own nature, which always leads away from God. Animals will only ever have their own natures. Therefore, neither have free will without God.
Protestants, on the other hand, have no sacraments to receive from valid clergy, so why do they even go to church? To glorify God, we all say. But is it?
Take out salvation and count the number of people who come to church on the fingers of one hand. No one goes to church to glorify God, but to seek favor, to assure salvation, life everlasting.
Judging our motives for going to church, eh? Not very Biblical, is it? :) Actually, none of us go to assure salvation because, from our perception, salvation occurs in a single moment in time. Our new, regenerated hearts tell us to obey God's will and go to church to worship God. We don't earn any God points for going, we go because we want to obey God, and yes, it is good for us. It is a primary means of sanctification, and we who have regenerated hearts all seek after it because we have a new nature.
But I doubt that you would ever honestly raise a sword to kill your children in good faith without questioning God (and thereby committing sin).
And I pray I never have to find out! :) But in today's modern world who could ever know with certainty how he would react. In Abraham's time God spoke directly to him in real words, a kind of a "burning bush" moment. I don't think that happens much today, and I know it has never happened to me. It's very hard to make a comparison. Of course, if I did agree to do it, it would not be because of the faith in me, it would be from strong enough faith given to me by God. We all honor Abraham for his faith, but it really came from God, not from himself.
No, we have our nature and our intellect. It is the intellect which is capable of free will, not your nature (flesh). Animals don't have the intellect. That's why they choose by necessity, and not by intellect.
And what if it was your insanity?