The most
  influential thinker in the formation of the Latin Christian tradition.
  Aurelius Augustinus began life at Tagaste in Roman Africa (Algeria) & died
  as bishop of Hippo, only 45 miles away. But his long personal spiritual
  journey left indelible marks on medieval & modern western culture.
  Though his mother
  was a Christian, Augustine himself did not join the Catholic church until he
  was 33. He began his career as a teacher of classic Latin rhetoric. His
  personal intellectual quest, recounted in his
  Confessions (397 CE), led
  him from Cicero to Manicheism to Neo-Platonism before he was baptized by
  Ambrose at Milan (Italy) in 387. He returned to Africa & in less than a
  decade was made bishop of Hippo, where he distinguished himself in debate with
  Manicheans & other sects, notably supporters of Pelagius, who claimed
  salvation depended on individual free will. Convinced that God had shaped the
  course of his own life, Augustine insisted that salvation depends on
  predestination, a view that he used to champion the triumph of Christianity
  over pagan Rome in his masterpiece, The
  City of God (427 CE). A
  prolific interpreter of scripture, Augustine formulated the doctrine of
  original sin & tried to demonstrate the Consensus
  of the Gospels, against
  those who claimed discrepancies between 
	Matthew, 
	Mark, 
	Luke & John
  invalidated their accounts.
  Augustine took for granted the
  order of the gospels in the NT
  was the order in which they were composed. Moreover,
  he assumed that each writer had read the work of every predecessor. Thus,
  Augustine was the first to recognize a direct literary dependence of one
  synoptic gospel upon another. Since he had such a great influence on later
  biblical interpreters, his comments in
  Consensus of the Gospels 1.2.4 deserve
  direct quotation:
  
    Although each of these [gospel
    writers] may appear to preserve a certain order of narration proper to
    himself, this certainly should not be taken as though each individual writer
    chose to write in ignorance of what his predecessor had done, or left out
    things, which nonetheless another (gospel) is discovered to have recorded,
    as matters about which there was no information. Rather, the fact is that as
    each of them received the gift of inspiration, they abstained from adding to
    their distinct works any extra shared compositions.
    For Matthew is understood to
    have undertaken to construct the record of the incarnation of the Lord
    according to the royal lineage, and to give an account of most of His words
    and deeds as they relate to this present human life.
    Mark follows him closely, and
    looks like his assistant and epitomizer. For in his narrative he gives
    nothing apart from the others that agrees with John. He has little to record
    distinctly on his own. He has still less in common with Luke that is
    distinct from the rest. But he has a very great number of passages in common
    with Matthew. He also narrates much in words almost the same in number and
    identity as those used by Matthew, where this agreement is either with that
    evangelist alone, or with him in connection with the rest.
    Luke, on the other hand, appears
    to have been concerned instead with the priestly lineage and character of
    the Lord. For although in his own way he takes [Jesus'] descent back to
    David, he has followed not the royal pedigree, but the line of those who
    were not kings. He has also traced that genealogy to a point in David's son
    Nathan, who likewise was no king. Yet, it was not so in Matthew. For in
    tracing the lineage through king Solomon, he has followed with strict
    regularity the succession of the other kings....
  
  Augustine's
  attempt to explain why the genealogy in Luke differed from the one in Matthew
  made him the first scholar to recognize that later gospels were creative
  revisions of earlier works. That is, gospels present not only additions to but
  deliberate alterations of their sources that reflect the themes stressed by
  their authors. This insight became the basis of  redaction
  criticism.
  Thus, Augustine's
  view (which became the prevailing opinion in western Christian tradition) is
  that:
  
    - Matthew wrote the basic
      story of Jesus' human life;
 
    - Mark condensed Matthew;
 
    - Luke edited Matthew &
      Mark, omitting passages they covered.
 
    - John wrote to fill in what
      the others omitted.
 
  
  This theory went
  unchallenged until the late 18th c., when J.
  B. Koppe pointed
  out that Augustine was wrong in claiming that the text of Mark had little in
  common with Luke.
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