Zippy,
I'm sure this has been stated to you before, but I will bring it up again just to be clear, that the Westminster Divines and the London Baptists as well as Martin Luther (and I believe Calvin) have all made the point that God's role in reprobation is a passive role. His role in saving the elect is active, but His role in hardening the lost is passive.
That the Bible says God hardened Pharaoh's heart is beyond dispute (Exodus 7:1-5). The question remains, how did God harden Pharaoh's heart? Luther argued for a passive rather than an active hardening. That is, God did not create fresh evil in Pharaoh's heart. There was already enough evil present in Pharaoh's heart to incline him to resist the will of God at every turn. All God ever has to do to harden anyone is to remove His restraining grace from them and give them over to their own evil impulses (Romans 1:28) This is what God does to everyone whom He passes over.
In an
essay on double predestination, R. C. Sproul quotes Francois Turrettini:
The negative act includes two, both preterition, by which in the election of some as well to glory as to grace, he neglected and slighted others, which is evident from the event of election, and negative desertion, by which he left them in the corrupt mass and in their misery; which, however, is as to be understood, 1. That they are not excepted from the laws of common providence, but remain subject to them, nor are immediately deprived of all God’s favor, but only of the saving and vivifying which is the fruit of election, 2. That preterition and desertion; not indeed from the nature of preterition and desertion itself, and the force of the denied grace itself, but from the nature of the corrupt free will, and the force of corruption in it; as he who does not cure the disease of a sick man, is not the cause per se of the disease, nor of the results flowing from it; so sins are the consequents, rather than the effects of reprobation, necessarily bringing about the futurition of the event, but yet not infusing nor producing the wickedness…
(Francois Turrettini, Theological Institutes (Typescript manuscript of Institutio Theologlae Elencticae, 3 vo]s., 1679-1685), trans. George Musgrave Giger, D.D., p. 97.)
Let's look at this particular part:
2. That preterition and desertion; not indeed from the nature of preterition and desertion itself, and the force of the denied grace itself, but from the nature of the corrupt free will, and the force of corruption in it; as he who does not cure the disease of a sick man, is not the cause per se of the disease, nor of the results flowing from it; so sins are the consequents, rather than the effects of reprobation, necessarily bringing about the futurition of the event, but yet not infusing nor producing the wickedness…
He says that (passive) reprobation necessarily brings about wickedness, but does not
cause that wickedness. Similarly, consider a plant in dire need of water. The gardener who refuses to water the plant does not
cause the death of the plant, even though he has the power to save it. Or take Turrettini's own analogy: a disease. The doctor who refuses to treat a disease causes neither the disease or the results of the disease, even though he has the power to cure it.
The problem is this: responsibility is destroyed. The plant is not at fault any more than the diseased person. He contracts a disease and dies from it. And is he to be punished for this? For the effects of the disease?
We can only punish someone if it is possible for them to avoid the fault. On Calvinism, God punishes man for the effects of a disease that man cannot cure, and this is true even on Infralapsarianism.
The second problem is this: God decided to let the man with the disease die even prior to foreknowledge of demerits. That is, before the man had done anything wrong God decided that he should die from the disease. And this is somehow said to display God's justice--man dying from a terminal disease. Of course this is manifestly
unjust.