Background – LFW and responsibility
Under LFW, we are the causal source of our choices (i.e. nothing causally predetermines our choices); we are responsible for our choices. There’s nowhere else to go to. We can’t back track to something else – we are responsible. Under CFW, since our actions are causally predetermined, we can trace back the cause of our actions to something outside of us. Thus, we keep searching for the source of our actions to find out what’s ultimately responsible. When Calvinists say God is the ultimate source, we say they make God ultimately responsible for sin. Even if God establishes a system in which only secondary causes get punished and the primary cause does not (as Calvinists suppose), that doesn’t change the fact that God is ultimately responsible for sin. The issue isn’t one of God’s power or sovereignty, it’s a matter of His goodness and holiness.