The second foundation: God's absolute decree predetermining good acts and permitting evil (Alvarez)
The second foundation on which they rest the certainty of God's knowledge of things that will happen contingently is the absolute decree of the divine will. In the same place Alvarez says that the certainty of God's knowledge of future contingents can also be drawn from another source. This is the absolute and efficacious decree of his will, which predetermines in detail every future thing, free ones included, with all their circumstances, if they are good, or permits them if they are evil.
To explain more clearly what this efficacious decree permitting evil is, he notes further on that God's infallible foreknowledge of sins presupposes two decrees on God's part. One is an absolute decree to produce the act of sin insofar as it is an act and a being. The other is a decree not to give efficacious help for avoiding the sin, that is, a decree to permit its wickedness, which is attributed to the created or defectible will alone.
In these two decrees, he says, all future sins are known with certainty. If God abandons the sinner and does not help him so that he will not fall, he will infallibly sin.
Latin
XXXII. Alterum fundamentum, quo niti existimant certitudinem divinae scientiae, respectu eorum quae sunt contingenter futura, est absolutum divinae voluntatis decretum. Nam potest etiam, inquit ibidem Alvarez, ex alio capite desumi certitudo scientiae divinae comparatione futurorum contingentium, nimirum ex decreto absoluto, & efficaci suae voluntatis praedeterminantis in particulari omnia futura, etiam libera, cum omnibus suis circumstantiis, si sunt bona, vel ea permittentis si sunt mala. Atque ut clarius explicet quid sit illud decretum efficax voluntatis divinae permittentis mala, Observat in sequentibus duplex decretum praesupponi ex parte Dei ad praescientiam infallibilem peccatorum. Alterum est decretum absolutum producendi actum peccati, in quantum actus & ens est: Alterum vero est decretum non dandi auxilium efficax ad vitandum peccatum, seu decretum permittendi ejus malitiam, quae soli voluntati creatae, seu defectibili tribuitur. Et in his duobus decretis affirmat certo cognosci omnia peccata futura, quoniam Deo deserente & non adjuvante, peccatorem ne cadat, infallibiliter est peccaturus.