“So then he has mercy on whomever he wills, and he hardens whomever he wills. You will say to me then, ‘Why does he still find fault? For who can resist his will?’ – Romans 9:18-19
From pp. 191-2 of John Piper’s “The Justification of God“:
To be sure, Pharaoh said, “No” to God’s command that he send the Israelites into the wilderness. This can reasonably be called “resisting” God (cf. Acts 7:51). But this is so obvious to everyone that it is utterly implausible that the objector would be affirming that no one has ever resisted God in this sense. Everyone has. But Paul’s point was that even this resistance is in one sense willed (9:18) by God as hardness. The objector sees clearly that Paul is saying: God wills that Pharaoh resist God’s own commands.7
This fact has compelled both exegetes and systematic theologians to speak of God’s will in two different senses. These two senses have sometimes been designated as God’s signified will and effectual will, or as God’s revealed will and secret will, or as his will of command and will of decree. What is important for us here is to note that it is the second member of each of these pairs which the objector says cannot be resisted. And indeed this is a necessary and legitimate inference from Paul’s teaching in Romans 9:14-18. Perhaps Paul chose the unusual [Greek word for will] in Romans 9:19b (although he had used [another] in 9:18) to stress what cannot be resisted is precisely the effectual will or decree of God. Probably the will referred to is the [”purpose”] of 9:11 which stands firm because it is established “apart from works” (9:12) and before Jacob and Esau were born (9:11).
Therefore, what the objector correctly sees is that God, not man, holds final sway even in the lives of unbelievers. But his premise is that, unless man has the power of self-determination over against God, his evil acts cannot justly be faulted, i.e. he cannot be judged as a sinner (cf. Romans 3:7). From this premise he opposes Paul’s description of how God acted with Pharaoh and by implication the way he acts with all people in all times. In all likelihood the historical reality behind this (formally familiar) objection is the same pharisaical standpoint countered by Paul in Romans 9:11, as described and located by Herhard Maier…
7 Even Forster and Marston would have to admit this in some cases because they think that after the fifth plague God gave Pharaoh “supernatural strength to continue with his evil path of rebellion” (God’s Strategy, 73). In other words it was in some sense God’s will that for four more plagues Pharaoh not let the people of Israel go. Nevertheless, even after God had willed not to let Israel go, “The Lord said to Moses: ‘God to Pharaoh and say to him, “Thus says the Lord, Let my people go!” ‘ ” (Exodus 8:1). So even in their scheme, Forster and Marston have to distinguish between God’s “will of command” and his “will of decree.”
Jonathan Edwards on the two wills:
“When a distinction is made between God’s revealed will and his secret will, or his will of command and decree, ‘will’ is certainly in that distinction taken in two senses. His will of decree, is not his will in the same sense as his will of command is. Therefore, it is no difficulty at all to suppose, that the one may be otherwise than the other: his will in both senses is his inclination. But when we say he wills virtue, or loves virtue, or the happiness of his creature; thereby is intended, that virtue, or the creature’s happiness, absolutely and simply considered, is agreeable to the inclination of his nature.
“His will of decree is, his inclination to a thing, not as to that thing absolutely and simply, but with respect to the universality of things, that have been, are or shall be. So God, though he hates a thing as it is simply, may incline to it with reference to the universality of things. Though he hates sin in itself, yet he may will to permit it, for the greater promotion of holiness in this universality, including all things, and at all times. So, though he has no inclination to a creature’s misery, considered absolutely, yet he may will it, for the greater promotion of happiness in this universality.” (>>)