III. Theology of St. Augustine
St. Augustine is regarded as one of the two greatest minds in the history of the Roman Catholic Church. His prodigious output of philosophical and theological works was the dominant influence on doctrine of the Roman Church for the thousand years until St. Thomas Aquinas and beyond until today.
It is paradoxical that this Doctor of the Church known for the power of his mind is equally well-known for the weakness of his flesh. That weakness impressed itself on his thought in a dominant way, especially on his view of human nature and on his formulation of the doctrine of original sin.
Augustine's views were influenced by the dualism of Manicheism, a religious philosophy to which Augustine adhered for nine years and later opposed. Long regarded as a Christian heresy but now understood as a complex gnostic religion, Manicheism held that light and dark, good and evil, are separate entities in conflict and regarded physical matter as dark and evil. [20, 21]
Augustine's views were also influenced by his study as a youth of Greek philosophy, which taught that destiny and fate are actual external forces in the universe that control human affairs. The Greeks likewise regarded sexual desire as a force beyond human control. 
It was as a youth of 16 that Augustine became sexually active and gave himself totally to sinful erotic pleasures.  Thenceforth until his spiritual conversion, he was unable to live without sexual gratification. However, contrary to common misconception, he was not a libertine. He sometimes only feigned debauchery to gain acceptance by his adolescent peers.  At the age of 17, he persuaded a Catholic girl to become his concubine.  After living faithfully for 15 years with this one woman by whom he had a son, he separated from her following a betrothal arranged by his mother, St. Monica. But the new girl was almost two years underage for marriage  and Augustine, addicted to sex, took another concubine to tide him over. [27, 28, 29]
During the interim, Augustine experienced a profound spiritual conversion  when he came upon Romans 13:13-14:
[L]et us live honorably as in the day, not in reveling and drunkenness, not in debauchery and licentiousness, not in quarreling and jealousy. Instead, put on the Lord Jesus Christ, and make no provision for the flesh, to gratify its desires.
Suddenly, he found it easy to give up his carnal way of life and began to pursue the knowledge and wisdom of God.  He returned to orthodox Christianity and soon became such a popular defender of the faith that he was summarily ordained against his will while attending Mass. [31, 32] Having begun a career as a writer of philosophical works, Augustine now turned his attention to theological matters -- a turn that changed the direction of the Church's teaching ever since.
During it's first three centuries, Christianity brought a message of moral freedom into an era of political repression and persecution. The Christian gospel proclaimed the dignity of each human person, even the slave, made in the image and likeness of God (Genesis 1:26) and the freedom of the will to choose moral behavior. Prominent writers, including Justin, Irenaeus, Tertullian, Clement, and Origen, unanimously upheld the orthodox Christian belief in the moral freedom of the human will against the Gnostic Christians who denied moral autonomy. 
Augustine himself, as a young man, wrote a treatise On Free Will praising human freedom. Years later, however, when he wrote his Confessions, he reversed his position and contended that we have no power to choose not to sin.  Augustine changed the positive, uplifting message of Christianity to a negative one of every person's enslavement to sin as a consequence of Adam's first sin. According to Augustine, Adam's sin corrupted human nature itself. Adam's descendants -- all of humanity -- share in the guilt of his sin and were consequently punished by God with physical death, domination by sexual desire, and impairment of the will to make moral choices. 
Augustine based his unorthodox (at the time) theory of original sin on a negative, one-sided interpretation of Genesis 1-3 and substantiated it with a singular interpretation of verses in Paul's letter to the Romans. In his letter, St. Paul attests to the universal personal sinfulness of all persons and redemption by Jesus Christ:
... since all have sinned and fall short of the glory of God; they are now justified by his grace as a gift through the redemption that is in Christ Jesus ... (Romans 3:23-24)
When Paul goes on to address Adam's sin, the only consequence to humanity he attributes to Adam's sin is the one specified in Genesis -- physical death:
Therefore, just as sin came into the world through one man, and death came through sin, and so death spread to all because [or: in that] all have sinned ... (Romans 5:12)
Nowhere does Paul conceive of Adam's transgression as the beginning of a process in which every generation transmits original sin to the next generation. He is, rather, concerned with a "communion of sinners" that has existed from the beginning but has been redeemed by Christ to be a "communion of saints." 
Augustine's claim on the authority of St. Paul to support his notion of original sin hangs on a single prepositional phrase in Romans 5:12. Augustine insisted that Paul referred to the one man, Adam, "in whom all sinned,"  but Augustine's Latin phrasing was a mistranslation of the Greek text "in that all sinned." [38, 39] The difference is profound. Augustine distorted a statement of universal personal sinfulness into a statement of universal complicity in Adam's first sin.
Augustine resorted more to authority than reason as the way to truth as his pessimistic view of fallen human nature developed.  But of five proof texts Augustine cited to support original sin, Kirwan maintains that three are mistranslations and the other two are misconstrued.  When his critics accused him of inventing original sin, he evaded responsibility by passing it on to his teachers, Cyprian and Ambrose. 
Augustine also adopted a negative view of sex in reaction to his previous life of uncontrolled gratification and the Church's valuing of sexual asceticism. Some early Christians held that carnal knowledge was conveyed by the forbidden fruit of the garden and that sex was accordingly sinful. In line with orthodox thought, however, Clement of Alexandria (early 3rd century) denounced such views and declared that sexual intercourse was an original part of God's creation. Those who engage in procreation are not sinning but "cooperating with God in his work of creation." 
But for Augustine, sex as we experience it is a corruption of nature. For him, the involuntariness of sexual arousal -- what he called "this diabolical excitement of the genitals"  -- is the clearest evidence of original sin. The body's ability to act without the will's intention, Augustine contended, shows a lack of integrity -- a privation he attributed to mankind's punishment for Adam's sin. 
Augustine's reasoning was distorted by his negative view of sex. His reading of Scripture does not uphold the natural goodness of God's heterosexual creation implicit in the command to "Be fruitful and multiply." (Genesis 1:28) For Augustine, sex is not only unnatural to man as originally created by God, but sinful even in marriage if directed to pleasure.  Intercourse in marriage is redeemed by intent of procreation, but it nevertheless remains the transmitter of sin. [47,48]
In his preoccupation with sexual matters, Augustine wrongly identified concupiscence with lust and considered this "bestial desire" to be evil.  Concupiscence encompasses the entire range of human appetites, according to Aquinas, not only of the physical senses but also of the emotions and intellect.  Human desires -- both "natural" and "rational" -- may be directed to something that is morally good or they may rise in opposition to our moral imperatives. Before, during, and after our moral choosing, concupiscence can be present as a countertension pulling us away from right behavior. 
It is concupiscence as proneness to sin that St. Paul speaks of when he acknowledges:
For I know that nothing good dwells within me, that is, in my flesh. I can will what is right, but I cannot do it. For I do not do the good I want, but the evil I do not want is what I do. ... I delight in the law of God in my inmost self, but I see in my members another law at war with the law of my mind, making me captive to the law of sin that dwells in my members. (Romans 7:18-19, 22-23)
When Paul says he can want what is right but not do it, he expresses the denial of reality all persons engage in at times. We want to "have our cake and eat it, too." Knowing what is good and right can be insufficient motivation to choose the right when something more alluring is pulling us away. We would like to be good, but we like something else more.
Adam and Eve's desire to eat the forbidden fruit because it was "good for food, and that it was a delight to the eyes, and that the tree was to be desired to make one wise" (Genesis 3:6) is itself a prime example of concupiscence. Because Adam could be tempted and could sin, as Rahner points out, spontaneous desire to evil as well as good must have been part of man's metaphysical nature even before the fall. Such natural concupiscence renders implausible the definition of an altered concupiscence corrupted by the fall that "is of more significance for moral decisions than those essential characteristics of man which independently of original sin and prior to it already provide the basis for his exposure to temptation and his power to sin." 
Augustine's radical view of human nature as fallen and corrupt provoked intense disagreement with various of his contemporaries, including John Chrysostom, Pelagius, and especially Julian of Eclanum. Pelagius and his followers, including Julian, denied the existence of original sin and maintained that the human will is completely free to choose good or evil.  Their views rested on God's own affirmation that he "saw everything that he had made, and indeed, it was very good." (Genesis 1:31).
Julian and Augustine disputed openly in a series of writings that continued until the end of Augustine's life and at times degenerated into mutual ad hominem attacks.  Julian held that mortality and sexual desire are natural to humans. The death God threatened for eating the fruit of the tree, he argued, is not physical death as a punishment, but spiritual death as a natural consequence of sin.  God himself told Adam and Eve the reason they would return to the ground is because they were taken from the ground. (Genesis 3:19)  Moreover, Julian's contrary experience of sex in a controlled manner (a bishop like Augustine, he was married to the daughter of a bishop) gave the lie to Augustine's blanket condemnation of human nature as perversely corrupt and incapable of willful control. Indeed, sexual desire offers us the opportunity to freely choose moral behavior.  Pelagius perceptively observed that habit (such as Augustine's pre-conversion sexual indulgence) can acquire what seems to be the force of nature. 
Julian accused Augustine of espousing the Manicheism of his youth, a charge supported by recent discoveries that show striking similarities between Augustine's positions on human nature and concupiscence and those of Manicheism.  In Manicheism, Adam and Eve are created from darkness; thus, human nature is inherently evil. Sexual reproduction is of demoniac origin; thus, salvation of the elect requires complete abstinence from sexual contact. 
Augustine taught that infants who die without baptism are damned to eternal fire.  By his time in the Christian era, the practice of infant baptism was so well established that he cited it as evidence of its necessity in support of his theory of original sin. However, the practice is not documented in historical writings before the latter half of the second century. There is no record from apostolic times regarding infant baptism. 
The custom of infant baptism seems to have developed in the first centuries of Christianity without any conscious thought regarding its necessity or lack thereof. The practice likely grew from a natural carrying out of Jesus' words to Nicodemus: "no one can enter the kingdom of God without being born of water and Spirit." (John 3:5) However, in addressing an adult, Jesus may have been directing his admonition to those capable of willful personal sin. Such an interpretation is consistent with his declaration: "Truly I tell you, unless you change and become like children, you will never enter the kingdom of heaven." (Matthew 18:3)
For Augustine, the very helplessness of an infant -- in contrast to animal young that can walk unaided and find their mother's milk as soon as they are born -- is a strong proof of the devastating effect of Adam's sin on human nature.  Augustine had no appreciation for the positive value of that very helplessness in fostering emotional bonding through the parents' nurturing. Can anyone who has known joy in the sweetness and innocence of an infant believe they come into existence alienated from the God who made them?
Augustine's condemnation of unbaptized children is diametrically opposed to Jesus' regard expressed to them:
People were bringing little children to him in order that he might touch them; and the disciples spoke sternly to them. But when Jesus saw this, he was indignant and said to them, "Let the little children come to me; do not stop them; for it is to such as these that the kingdom of God belongs. Truly I tell you, whoever does not receive the kingdom of God as a little child will never enter it. And he took them up in his arms, laid his hands on them, and blessed them. (Mark 10:13-16; also Matthew 19:13-15, Luke 18:15-17)
Jesus virtually canonized the little children -- the unbaptized little children -- when he said, "it is to such as these that the kingdom of God belongs."
Some argue this encounter with the children is an indirect allusion to the baptism of children. The children are to be allowed to come to Jesus through baptism rather than stopped or hindered. 
There are two problems with such an interpretation. Firstly, it flies in the face of the disciples' behavior in "stopping," which itself demonstrates the absence of any sense of ministry to children. Secondly and more decisively, it assumes the availability of morally efficacious baptism. Although Augustine and Aquinas both ascribe an efficacious quality to the baptism Jesus' disciples practiced (John 4:2) contemporaneously with John's baptism of repentance, baptism "in water and Spirit" did not begin until Pentecost. In the first Christian treatise on baptism, written ca. 200, Tertullian references John 7:39 in asserting:
at that time, of course, [baptism for the remission of sins] could not be given by His disciples, inasmuch as the glory of the Lord had not yet been fully attained, nor the efficacy of the font established through the passion and the resurrection. 
As "a moral purification effected by the power of Christ's redemptive action," sacramental baptism could not have preceded Jesus' passion, death, and resurrection. 
Moreover, Tertullian -- one century following apostolic times and one century preceding Christianity's assimilation of imperial secular mores -- avers that baptism before the age of reason is unnecessary:
And so, according to the circumstances and disposition, and even age, of each individual, the delay of baptism is preferable; principally, however, in the case of little children. ... The Lord does indeed say, "Forbid them not to come unto me." Let them "come," then, while they are growing up; let them "come" while they are learning, while they are learning whither to come; let them become Christians when they have become able to know Christ. Why does the innocent period of life hasten to the "remission of sins"? 
For Pelagius and Julian, also, who denied the existence of original sin, baptism of infants was unnecessary. Indeed, baptism's purported removal of original sin has no basis in Scripture or in experience. The absence of any observable effect is attested to by the life of Augustine himself. Baptism was an emotionally moving experience for Augustine. He felt at peace with his past life -- at least for the moment -- and wept.  However, it was not baptism that produced his profound conversion and delivered him from the bonds of addiction to sex, but a particular grace that predated his baptism. Augustine himself recognized that the baptized Christian continues to experience the same difficulty as the pagan in willing to choose good. 
For reasons that may have been as much political as theological,  the Roman Church ultimately sided with Augustine and rejected the views of Pelagius and Julian as heretical. The subsequent pervasive influence of Augustine's views on theology, however, was limited to the Latin-speaking Western Church. Although the teachings of the Greek-speaking Eastern Church (where important early Councils took place) were translated into Latin, the reverse was not the case. Augustine's works were not translated into Greek at the time, and so the Eastern church was not influenced by them.  Augustine himself knew little Greek, a language he resisted learning in school despite repeated floggings. 
Hence, in the Eastern Orthodox Church there is no "original sin." The Eastern Church remained true to the previous orthodoxy, which emphasized the positiveness of God's grace active in creation, and rejected as erroneous Augustine's theology of hereditary moral guilt. What was lost in the fall, according to Eastern orthodoxy, was the ability to obey God properly; but the Old Testament repudiates the very idea of transferable guilt: 
Parents shall not be put to death for their children, nor shall children be put to death for their parents; only for their own crimes may persons be put to death. (Deuteronomy 24:16)
After contaminating innocent infants with adult guilt, Augustine ultimately adopted a deterministic belief in predestination. Augustine held that grace has an infallible efficacy,  from which he concluded that God gives such grace only to a few persons chosen in advance to be saved whereas the rest are relegated to a deserved eternal damnation. [74, 75]
Augustine's view makes God less than infinite because it puts limits on God's love. Jesus put no such limitation on the promise of eternal life when he said:
I am the resurrection and the life. Those who believe in me, even though they die, will live, and everyone who lives and believes in me will never die. (John 11:25-26)
Predestinationism, which denies the freedom of the will under the influence of efficacious grace, has been condemned by Church Councils as heretical.  Some have argued that Augustine's views on the subject were misunderstood and misinterpreted.