Natural not as part of man's essence but as created with him, like the body's proportion and beauty
They further maintain that this righteousness was natural to the first man before the fall and should be called natural. They do not mean that it was a part making up the essence of human nature, or that it flowed necessarily from the principles of human nature. They mean that it was created together with that nature and belonged to the native endowments of human nature before the fall. On their teaching, then, original righteousness was a natural gift, not a supernatural one.
It stood to the soul of unfallen man as the due proportion and beauty of the limbs, their strength and grace, then stood to his body. Those belonged to a natural, not a supernatural, perfection of man, even though they were not part of his essence and did not flow necessarily from the principles of human nature.
Latin
XXVI. Porro justitiam istam primo homini ante lapsum naturalem fuisse, & dici debere contendunt. Non quidem quod fuerit pars essentiam naturae humanae constituens, aut quod ex humanae naturae principiis necessario fluxerit: sed quia fuit aliquid naturae concreatum, & ad dotes nativas humanae naturae nondum lapsae pertinens. Adeoque justitia illa Originalis, secundum eorum doctrinam, donum naturale fuit, non supernaturale. Et se habet respectu animae hominis integri, quomodo respectu corporis se habebat justa membrorum proportio & pulchritudo, vigor atque decor, quae in eo tum reperiebantur, quaeque naturalem quandam, non vero supernaturalem perfectionem hominis spectabant: licet non essent de essentia hominis, neque etiam ex naturae humanae principiis necessario fluerent.