So we have Dr. Z, weeping into his glass of brandy, no longer able to affirm the proposition God exists, a proposition which on the reading of Romans 1 that has been presented to us, a person can only deny if they are in some sense in sinful rebellion against the knowledge of God that is present before them.
It seems to me that a judgment that Dr. Z is sinful at T1 for stating his inability to affirm the proposition “God exists” is indefensible. Just as triceratops frill in T-Rex dung forces a rereading of Genesis 1, so cases like Dr. Z force a rereading of Romans 1. Who disagrees?
Let’s say that a person concedes that at T1 Dr. Z nonculpably fails to affirm the proposition “God exists”. That is a moment of disbelief. Let’s say that moment extends into a minute. Does that prolonged period of time suddenly make his state of disbelief sinful? (Is a minute just too long to disbelieve?) What about if it is prolonged an hour? Over night? For a month or two? If Dr. Z can nonculpably fail to affirm “God exists” for a moment then how long can he continue to do so before he is culpable for failing to do so?
These are straightforward questions and they invite straightforward answers.
