There is no logical contradiction entailed by God's creating only persons who are both essentially free and are saints (i.e. persons with “the property of being such that there are some occasions on which one has a capacity for wrongdoing and no occasions on which one in fact does wrong.”1This is relevant because...
Antony Flew: “If there is no contradiction here then Omnipotence might have made a world inhabited by perfectly virtuous people.”2
But so what if there is no contradiction? Something can be metaphysically impossible and/or not feasible for God while simultaneously not entailing a contradiction.3