St. Augustine, who became bishop of Hippo in North Africa and the
greatest theologian of Western Christianity, had a very hard time as a
young man with sexual lust. His “Confessions” are a classic of
spirituality. His mother St. Monica.Saint Augustine, born in what is now Souk-Ahras, Algeria, in AD
354, brought a systematic method of philosophy to Christian theology.
Augustine taught rhetoric in the ancient cities of Carthage, Rome, and
Milan before his Christian baptism in 387. His discussions of the
knowledge of truth and of the existence of God drew from the Bible and
from the philosophers of ancient Greece. A vigorous advocate of Roman
Catholicism, Augustine developed many of his doctrines while attempting
to resolve theological conflicts with Donatism and Pelagianism, two heretical Christian movements.
Source: The Bettmann Archive
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Teaching of St. Augustine of Hippo "a philosophical and theological philosophers of past centuries and modern times, he is the equal of them all; among theologians he is undeniably the first, and such has been his influence that none of the Fathers, Scholastics, or Reformers has surpassed it." (Philip Schaff, History of the Christian Church) Elsewhere, we have discussed his life and his writings; here, we shall treat of his teaching and influence in three sections: genius of the first order, dominating, like a pyramid, antiquity and the succeeding ages. Compared with the great

I. His Function as a Doctor of the Church
II. His System of Grace
III. Augustinism in History
https://www.newadvent.org/cathen/02091a.htm
EXCERPT:
Here are the main lines of this theory: The will never decides without a motive, without the attraction of some good which it perceives in the object. Now, although the will
may be free in presence of every motive, still, as a matter of fact it
takes different resolutions according to the different motives
presented to it. In that is the whole secret of the influence
exercised, for instance, by eloquence (the orator can do no more than
present motives), bymeditation, or by good reading. What a power over the will
would not a man possess who could, at his own pleasure, at any moment,
and in the most striking manner, present this or the other motive ofaction? -- But such is God's privilege. St. Augustine has remarked that man is not the master of his first thoughts;
he can exert an influence on the course of his reflections, but he
himself cannot determine the objects, the images, and, consequently,
the motives which present themselves to hismind. Now, as chance is only a word, it is God who determines at His pleasure these first perceptions of men, either by the prepared providential action of exterior causes, or interiorly by a Divine illumination given to the soul. -- let us take one last step with Augustine: Not only does God send at His pleasure those attractive motives which inspire the will with its determinations, but, before choosing between these illuminations of the natural and the supernatural order, God knows the response which the soul, with all freedom, will make to each of them.
Thus, in the Divine knowledge, there is for each created will an indefinite series of motives which de facto (but very freely) win the consent to what is good. God, therefore, can, at His pleasure, obtain the salvation of Judas, if He wishes, or let Peter go down to perdition. No freedom, as a matter of fact, will resist what He has planned, although it always keeps the power of going to perdition. Consequently, it is God alone, in His perfect independence, who determines, by the choice of such a motive or such an inspiration (of which he knows the future influence), whether the will is going to decide for good or for evil. Hence, the man who has acted well must thank God for having sent him an inspiration which was foreseen to be efficacious, while that favour has been denied to another. A fortiori, every one of the elect owes it to the Divine goodness alone that he has received a series of graces which God saw to be infallibly, though freely, bound up with final perseverance.
continues concepts and discussion on God's Will....