Third and commonest opinion: no precept kept without special grace under grave temptation, but easier works can be
Far more common in the Roman School is a third view. It holds that man in the state of corruption cannot, without the special help of divine grace, keep the precepts of the natural law, either all together or even one by one, because some of them exceed the strength of corrupt nature: such as the precept against coveting, and the command to love God as the author of nature with all our heart. Those who hold this view admit that under grave temptation no commandment of the moral law can be fulfilled and no moral good achieved.
But when no grave temptation arises, they maintain that with God's general concurrence alone, without any particular help of grace, the easier works of the moral law can be kept as to the substance of the work in such a way that every new sin is avoided.
For example, a man not moved beforehand by any inward grace from God can honour his parents, help the needy, answer truthfully when asked, and return a deposit to a friend. He does it not from corrupt desire, for then the acts would be vicious, but from a natural inclination that is not evil; and not for a bad end, but simply because he judges it reasonable and part of his duty. On that basis they hold that such an act contains no sin and is truly morally good and honourable, though it does nothing for eternal salvation and merits neither grace nor glory in any way.
Latin
XVI. Sed in Schola Romana longe communior est tertia quaedam sententia. Illa statuit hominem in statu corruptionis, absque speciali gratiae divinae auxilio, servare non posse legis naturalis praecepta, nec omnia collective, nec etiam singula seorsim: quoniam inter illa sunt quae vires naturae corruptae superant: quale est praeceptum de non concupiscendo, & illud quo jubemur Deum ut authorem naturae ex toto corde diligere. Imo urgente gravi tentatione, qui sunt in hac sententia fatentur, nullum mandatum legis moralis impleri, nec ullum morale bonum perfici posse. Sed quum nulla gravis tentatio occurrit, pertendunt cum solo Dei concursu generali, & absque peculiari gratiae auxilio, opera legis moralis faciliora sic, quoad substantiam operis, servari posse, ut omne novum peccatum vitetur. Exempli causa, aliquem nulla interiori gratia a Deo praeventum, posse parentibus honorem exhibere, egenti subvenire, interrogatum vera respondere, depositum amico reddere; non ex prava cupiditate, quo in casu actiones illae vitio non carerent, sed ex naturali quadam propensione non mala: nec etiam in malum aliquem finem, sed simpliciter quia id judicat rationi consentaneum, & ad officium suum pertinere. Quo posito, existimant ejusmodi actionem nullum peccatum in se includere, sed revera moraliter bonam & honestam esse, quanquam ad salutem aeternam nihil prosit: nec sit gratiae, vel gloriae ullo modo meritoria.