Grace opposed to nature: owed neither to merit nor to nature
Thesis IV. In this sense grace is set against nature. The gifts God confers on us above nature are free in a special way: they do not fall under the person's merit, and they are not owed to nature either.
God, absolutely speaking, owes nothing to anyone and is bound to nothing. Yet once he wills that a creature should exist and act, he must in a way supply it with whatever it cannot exist or act without.
Latin
IV. Et hoc sensu gratia opponitur naturae. Quoniam illa dona quae nobis supra naturam a Deo conferuntur, singulari quodam modo gratuita sunt: quia, scilicet, non tantum sub meritum personae non cadunt, sed neque naturae debentur. Quamvis enim Deus absolute nihil cuiquam debeat, neque ad quicquam obligetur, tamen ex hypothesi quod creaturam velit esse & operari, illi quodammodo ea praestare debet, sine quibus nec esse, nec operari potest.