This chapter explores the constraints that a commitment to the inevitability of sin places on an understanding of the existence and nature of human freedom, and the implications of this understanding for debates about divine providence. It is argued, first, that the New Testament univocally attests to the inevitability of sin, and second, that given this biblical witness, Christians should not be swayed by one reason commonly given for rejecting theological determinism: in order to preserve libertarian freedom for humans at large. Still, considerations regarding the inevitability of human sin leave untouched another common argument against theological determinism: that it makes God the author of sin. Considerations of the inevitability (and culpability) of sin, on the one hand, and concerns about divine authorship of sin, on the other, might push one toward an uncommon combination of compatibilism and theological indeterminism. However, given the apparent unfairness of punishing individuals for sins they could not have avoided committing, a position between standard compatibilism and free will skepticism is tentatively endorsed.