within human being, not a clash of opposing, independent substances (c. Jul. imp. 5.30; Gn. litt. 10.12.20). The clash between flesh and spirit is not “natural,” but the result of the prior sin of pride (conf. 2.2.2; 7.7.1; 8.5.10), a disorder brought on the mind by itself in its revolt against God. Out of this struggle arises moral impotence; concupiscence is beyond the will’s purview and resists integration. Yet raw willpower is insufficient; the help of God’s grace, a sheer gratuity, can alone