V. SOURCES OF THE GOSPEL; SYNOPTIC PROBLEM
The best information as to his sources is given by St. Luke, in the beginning of his Gospel. As many had written accounts as they heard them from "eyewitnesses and ministers of the word", it seemed good to him also, having diligently attained to all things from the beginning, to write an ordered narrative. He had two sources of information, then, eyewitnesses (including Apostles) and written documents taken down from the words of eyewitnesses. The accuracy of these documents he was in a position to test by his knowledge of the character of the writers, and by comparing them with the actual words of the Apostles and other eyewitnesses.

That he used written documents seems evident on comparing his Gospel with the other two Synoptic Gospels, Matthew and Mark. All three frequently agree even in minute details, but in other respects there is often a remarkable divergence, and to explain these phenomena is the Synoptic Problem. St. Matthew and St. Luke alone give an account of the infancy of Christ, both accounts are independent. But when they begin the public preaching they describe it in the same way, here agreeing with St. Mark. When St. Mark ends, the two others again diverge. They agree in the main both in matter and arrangement within the limits covered by St. Mark, whose order they generally follow. Frequently all agree in the order of the narrative, but, where two agree, Mark and Luke agree against the order of Matthew, or Mark and Matthew agree against the order of Luke; Mark is always in the majority, and it is not proved that the other two ever agree against the order followed by him. Within the limits of the ground covered by St. Mark, the two other Gospels have several sections in common not found in St. Mark, consisting for the most part of discourses, and there is a closer resemblance between them than between any two Gospels where the three go over the same ground. The whole of St. Mark is practically contained in the other two. St. Matthew and St. Luke have large sections peculiar to themselves, such as the different accounts of the infancy, and the journeys towards Jerusalem in St. Luke. The parallel records have remarkable verbal coincidences. Sometimes the Greek phrases are identical, sometimes but slightly different, and again more divergent. There are various theories to explain the fact of the matter and language common to the Evangelists. Some hold that it is due to the oral teaching of the Apostles, which soon became stereotyped from constant repetition. Others hold that it is due to written sources, taken down from such teaching. Others, again, strongly maintain that Matthew and Luke used Mark or a written source extremely like it. In that case, we have evidence how very closely they kept to the original. The agreement between the discourses given by St. Luke and St. Matthew is accounted for, by some authors, by saying that both embodied the discourses of Christ that had been collected and originally written in Aramaic by St. Matthew. The long narratives of St. Luke not found in these two documents are, it is said, accounted for by his employment of what he knew to be other reliable sources, either oral or written. (The question is concisely but clearly stated by Peake "A Critical Introduction to the New Testament", London, 1909, 101. Several other works on the subject are given in the literature at the end of this article.)

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if you want to read more...
http://www.newadvent.org/cathen/09420a.htm

interesting

It would be obviously futile for me to present myself as an intellect. But sometimes we can complicate a thing. A dozen people can witness the same event, and all present a different aspect, and still none be in conflict with another. Did you ever read that poem about the group of blind men fron Hindustan who went to see the elephant, tho all were blind? One felt the tail and said he knew the elephant was like a rope. Each, in turn, felt(or witnessed)a different part of the elephant and made a decision as to what the elephant looked like. They were each right according to their personal witness. Without someone there to correct and instruct them, to pull each observation together, they were wrong, even while they were right. Every man who wrote in the Bible was guided by the Holy Spirit. Paul spoke of what he personally saw and heard, as did the rest. Without the Spirit, there is incomplete truth or downright false belief. No man can understand Truth without the Spirit. Intellectualism is no help without it. Great intellects accept the Bible as the unerrant Word of God, and so do simple-minded or uneducated people. Thank God! That's why there's hope for me! Without the Bible, or with the inclusion of any other book deemed on par with or superceed it, a religion, according to the Bible itsself, cannot be Christian. I refer you to "Evidence That Demands a Verdict", "Kingdom of the Cults", and "A Ready Defense". Dr. Walter Martin and Josh McDowell, are highly intelligent men and great apologists. Another is Dr. KP Yohannan, from India.

Great write my new gal pal.......and I love love using the above books for references of why that particular religion is a cult.....All of the above....great reads....especially "Kingdom of the Cults", I especially like the story on the man who started satanism.....and the irony of what happen with his life....