Bonum et malum in actibus voluntatis proprie attenditur secundum obiecta, quia differentia speciei in actibus est secundum obiecta, ut dictum est.
Good and evil in the acts of the will is derived properly from the objects, because the specific difference in acts is according to objects, as stated above (q18 a5).
Ergo bonitas voluntatis est ex hoc quod aliquis vult bonum.
Therefore the goodness of the will is from the fact that a man wills that which is good.
Voluntas non semper est veri boni, sed quandoque est apparentis boni, quod quidem habet aliquam rationem boni, non tamen simpliciter convenientis ad appetendum. Et propter hoc actus voluntatis non est bonus semper, sed aliquando malus.
The will is not always directed to what is truly good, but sometimes to the apparent good, which has indeed some formal aspect of good, but not of a good that is simply suitable to be desired. Hence it is that the act of the will is not always good, but sometimes evil.
Bonum per rationem repraesentatur voluntati ut obiectum; et inquantum cadit sub ordine rationis, pertinet ad genus moris, et causat bonitatem moralem in actu voluntatis. Ratio enim principium est humanorum et moralium actuum, ut supra dictum est.
Good, according to its formal aspect, is presented to the will as its object; and insofar as an object falls under the order of formal aspect, it enters the moral order, and causes moral goodness in the act of the will, since formal aspect is the principle of human and moral acts, as stated above (q18 a5).