The books of the New Testament are the classical literature of Christianity in a much fuller and more obvious sense. Here, again, there is much that apart from the use of a good commentary will be found hardly intelligible: but the greater part of the New Testament, and especially the Gospels, can be read with profit by the ordinary man apart from any extraneous aids. It is well to remember that S. Paul's Epistles were written at an earlier date than any of the Gospels, and that they represent the occasional correspondence of a hard-worked missionary. Of the Gospels the first three have much in common, and the Gospels of S. Matthew and S. Luke are based partly upon that of S. Mark. S. Mark is said to have been the companion of S. Peter, and is probably the author of the Gospel which bears his name. It may be taken to represent his reminiscences of S. Peter's preaching. The Gospel now known as that according to S. Matthew appears to be the work of a compiler who fitted into the framework of S. Mark's story a considerable amount of additional matter, drawn chiefly from a collection of "sayings of Jesus" which an early Christian writer declares to have been made by S. Matthew in Aramaic. S. Matthew's name, it is thought, was subsequently attached to the resulting document, since it contained a large preponderance of material derived from his book on our Lord's sayings. The name of the actual compiler of the first Gospel has not survived. S. Luke's Gospel is a compilation made upon somewhat similar lines, and is based, in large measure, upon the same two sources: but the author's researches extended also more widely, and his Gospel contains a large proportion of matter peculiar to itself, which critics commonly regard as being of high historical value. The author of the book was a Greek doctor who attended upon S. Paul, accompanying the latter in his travels, and writing the Acts of the Apostles as a second volume in continuation of his Gospel. The Acts is partly based upon a kind of diary which S. Luke kept of his experiences as S. Paul's companion and physician. It is probable that both the first and the third of our four Gospels were in existence shortly before, or at the latest very shortly after, the destruction of Jerusalem by the Romans in the year 70 A.D. The second Gospel, since they both drew upon it, must be even earlier.