Where the acts of unbelievers and of believers belong
Thesis XVIII. The acts of unbelievers that look honourable and seem to come from virtue belong to the first kind. As we said above, they do not come from faith and the love of God, and they are not directed to God's glory, so they cannot be counted among good and holy works or simply be called such.
The actions of believers, done with the help of the Holy Spirit and by Christ's grace, belong to the second kind. They are good not only in their object and substance but also in their source and their end, since they are done out of love and aim at God's glory.
That is why such works of believers are approved and accepted by God as truly and properly good, and should be called good simply and without qualification, even though they do not have every kind of goodness and fall well short of the highest perfection.
Latin
XVIII. Ad prius genus pertinent actus infidelium qui videntur honesti & ex virtute profecti. Non enim ex fide promanant, & ex Dei amore, nec etiam ad Dei gloriam referuntur, ut supra jam diximus, ac proinde non possunt inter opera bona & sancta numerari, & talia dici simpliciter. Actiones vero fidelium auxilio Spiritus sancti, & per Christi gratiam factae, ad alterum istud genus referri debent: siquidem non tantum bonae sunt ratione objecti, & quoad substantiam, sed etiam ratione principii & finis, quandoquidem ex charitate fiunt, & tendunt ad Dei gloriam. Ideoque ejusmodi fidelium opera Deo probantur atque accepta sunt, ut vere & proprie bona, & talia simpliciter & absolute loquendo dici debent: licet non omnimodam bonitatem habeant, neque parum a summa perfectione deficiant.