Gospel of Luke
The Gospel According to Luke, also known as The Gospel of Luke, is the third (traditionally) of the four canonical gospels of the New Testament and also the longest. It is also considered one of the three synoptic gospels. It was likely written sometime between 75-100 CE and probably the last of the synoptic gospels to be written.
There are several places in Luke where the narrative in Mark has added detail inserted before it returns back to the original Mark based events. For example when he calls Simon (Peter) and Andrew for the first time to be “fishers of men” (Mark 1:16-18 , Matthew 4:18-20 ) they “straightway” follow Jesus. But in Luke, he talks to Simon on his own and Jesus does a quick fishing trip miracle (Luke 5:1-8 ) which is serves as a parable instead of a literal statement. So this is an example of a simple event narrative being expanded to being a dual purpose story/parable. (Or somehow both versions are literally true, which seems unlikely. Two separate events?) Similar expansions and insertions are used for love thy neighbour and the parable of the good Samaritan (Luke 10:29-37 ), an angel appearing at the mount of olives (Luke 22:44 ), Jesus talking to the other two being crucified (Luke 22:39-43 ) and Jesus meeting Herod (Luke 23:7-9 ) (this seems particularly arbitrary).
Some of the strongest anti-materialism statements are found in Luke: Luke 14:33 , Luke 12:33 , Luke 6:24 , (rich man told to sell up) Luke 18:22 . This is also backed up by Jesus’s example in life. This could not be much clearer!
The point at the end of the parable of Lazarus is strange:
"And he said unto him, If they hear not Moses and the prophets, neither will they be persuaded, though one rose from the dead."
Which implies Jesus did not expect his resurrection to be persuasive, which contradicts Christians trying to use it as a tool for prosthelytizing.
Prophesy gets a good watering down in Luke:
"And when he was demanded of the Pharisees, when the kingdom of God should come, he answered them and said, The kingdom of God cometh not with observation: Neither shall they say, Lo here! or, lo there! for, behold, the kingdom of God is within you."
They probably became bored of waiting for the earlier predictions in Mark 8:38-9:1 and Matthew 16:27-28 . This also makes the kingdom a perspective rather than an event or place. This allows a great number of metaphysical inventions to escape their own failed predictions.
Finally, Jesus’s last words before death are not consistent across gospels. Biblical literalists have a particularly poor response on this conflict: they claim that all three are true but each narrative omits details. This is done because each author has a different “perspective”. This is pretty much an admission that the gospels are not literally true.
Historians virtually all agree that authorship of Luke took place before c. 150 due to the presence of widespread quotes and references to Luke in other early manuscripts from the latter half of the second century. Furthermore, the earliest church fathers, as well as the majority of historians through time up to the present, generally still date Luke to around c. 75-100. The lower bound to this range arose primarily due to the textual parallels in Luke that indicate this author used Mark as a source and also the general sense that the details about the Temple's destruction mentioned in Luke 21:5-30 (where Jesus merely foretells of the coming destruction of the Temple) are sufficiently strong to indicate Luke was probably a witness to the destruction in c. 70, or working from a source written by a witness. The upper bound arose out of the assumption that the heretical Gospel of Marcion, which was likely formulated and written in the early half of the 2nd century, seemed undeniably based upon Luke, though no direct reference to Luke was ever made in the Gospel of Marcion.
However, one revisionist view still persists today among a minority of scholars, which states this situation might be the reverse -- that Luke may be based on Marcion. This alternative theory proposed that Marcion may have used the same primary synoptic source that Luke is thought to have used (that is, the Gospels of Mark) rather than using Luke directly. Furthermore, the undeniable parallels that exist between Luke and Marcion thus might have arisen out of Luke using Marcion (as well as Mark) -- rather than the other way around -- as an attempt by the author of Luke to "undue" the damage created by the heretical Gospel of Marcion that was competing strongly with church doctrine during the middle of the second century. If the latter hypothesis is true, the date of authorship for Luke would likely closer to c. 150, when the Gospel of Marcion was in wide distribution.
A minority of historians also assert that Luke may have been written before c. 75. These views are based primarily upon negative evidence. Other than the reference to the premonition mentioned above, the author of Luke failed to mention anything that occurred historically after c. 67 -- such as the deaths of prominent Christians, like Jesus' brother James or Luke's long time friend, Paul, or Peter, or any of the persecutions by Nero of Christian leadership that all took place after c. 64 (according to Tacitus). In addition, Luke also does not mention anything about the destruction of Jerusalem that occurred at this same time as the Temple destruction in c. 70. Of course, such omissions might also indicate that Luke was written long after these events took place, rather than before, and if written as a counter-balancing view of another work (such as the Gospel of Marcion), or a reworking of another work (such as the earlier Gospel of Mark) such circumstances could easily explain why such events do not appear in Luke. There is no evidence that the Gospels ever attempted to record historical events, so omission of significant events such as these is hardly a strong rationale to use for the dating of authorship.
In any case, the oldest existing manuscript today of the Gospel of Luke dates to around C. 200.
Textual Similarities & Scriptural Parallels
Text analyses has strong evidence to support the theory that whoever wrote the Gospel of Luke, likely authored the Book of Acts in the New Testament too.
The historical community is near equally divided over who likely was the actual author of Luke. Traditionally (and unanimously among religiously practicing scholars) the physician, and early Christian writer known as Luke the Evangelist, who was the primary companion to Paul during his travels, is attributed with authorship of this gospel. There is some sparse and weak evidence to support this hypothesis. Foremost, of the two earliest manuscripts we have, one has an attribution "According to Luke" actually written in it (which is rare in ancient Christian manuscripts, especially when they are written by anonymous authors). Another piece of circumstantial evidence points to how the author refers to Paul in his writings by the first person plural, which indicates the author was likely a companion to Paul. Other scholars have felt the use of language in both Luke and Acts (which have common authorship) connotes medical terminology, which hints that the author likely had medical training. Luke the Evangelist has been widely cited in several ancient sources, as being a physician.
Due to the minimal nature of this evidence, and given the tendency of early Christians to forge such documents on a regular basis and attribute them to famous Christian leaders of their day, many historians still doubt this attribution.
- Main Article: Many accurate copies of my holy book exist
Some of the earliest surviving Bibles dating from the 300's, like the Codex Sinaiticus (also called א or Aleph) and the Codex Vaticanus (also called B), are important examples of early manuscripts. The modern text of the New Testament contain later insertions which are not in these early versions.   The following sections are in neither early text and are therefore likely forgeries:
- Luke 9:55-56 "and said, Ye know not what manner of spirit ye are of. For the Son of man is not come to destroy men's lives, but to save them." 
- Luke 17:36 "Two men will be in the field; one will be taken and the other will be left." 
- Luke 23:17 "Now he was obliged to release to them at the feast one prisoner."