The Predestination of the Saints/Gift of Perseverance

Accordingly, as says the apostle, “It is not of him that wills, nor of him that runs, but of God that shows mercy,” who both comes to the help of such infants as He will, although they neither will nor run, since He chose them in Christ before the foundation of the world as those to whom He intended to give His grace freely—that is, with no merits of theirs, either of faith or of works, preceding; and does not come to the help of those who are more mature, although He foresaw that they would believe His miracles if they should be done among them, because He wills not to come to their help, since in His predestination He, secretly indeed, but yet righteously, has otherwise determined concerning them.

For “there is no unrighteousness with God;” but “His judgments are unsearchable, and His ways are past finding out; all the ways of the Lord are mercy and truth.” Therefore the mercy is past finding out by which He has mercy on whom He will, no merits of his own preceding; and the truth is unsearchable by which He hardens whom He will, even although his merits may have preceded, but merits for the most part common to him with the man on whom He has mercy. As of two twins, of which one is taken and the other left, the end is unequal, while the deserts are common, yet in these the one is in such wise delivered by God's great goodness, that the other is condemned by no injustice of God's.

For is there unrighteousness with God? Away with the thought! But His ways are past finding out. Therefore let us believe in His mercy in the case of those who are delivered, and in His truth in the case of those who are punished, without any hesitation; and let us not endeavour to look into that which is inscrutable, nor to trace that which cannot be found out. Because out of the mouth of babes and sucklings He perfects His praise, so that what we see in those whose deliverance is preceded by no good deservings of theirs, and in those whose condemnation is only preceded by original sin, common alike to both—this we by no means shrink from as occurring in the case of grown-up people, that is, because we do not think either that grace is given to any one according to his own merits, or that any one is punished except for his own merits, whether they are alike who are delivered and who are punished, or have unequal degrees of evil; so that he who thinks he stands may take heed lest he fall, and he who glories may glory not in himself, but in the Lord.