“Following the custom of the Synagogue, the Scriptures of the Old Testament were read at the primitive Christian assemblies. According as the Canon of the New Testament was decided on, certain extracts from it were included in these readings. Justin tells us that in his day, when the Christians met together, they read the Memoirs of the Apostles and the writings of the Prophets (First Apology 67). Tertullian, Cyprian, and other writers bear witness to the same custom; and in the West the order of lector existed as early as the third century. For want of precise testimony we do not know how the particular passages were decided on. Most likely the presiding bishop chose them at the assembly itself; and it is obvious that on the occurrence of certain festivals the Scripture relating to them would be read. Little by little a more or less definite list would naturally result from this method. St. John Chrysostom in a homily delivered at Antioch exhorts his hearers to read beforehand the Scripture passages to be read and commented on in the Office of the day (Homilia de Lazaro, iii, c. i). In like manner other Churches would form a table of readings. In the margin of the manuscript text it was customary to note the Sunday or festival on which that particular passage would be read, and at the end of the manuscript, the list of such passages, the Synaxarium or Capitulare, would be added. Transition from this process to the making of an Evangeliarium, or collection of all such passages, was easy. Gregory is of opinion that we possess fragments of Evangeliaria in Greek dating from the fourth, fifth, and sixth centuries, and that we have very many from the ninth century onwards (according to Gregory they number 1072). In like manner, we find Lectionaries in the Lain Churches as early as the fifth century. The Comes of the Roman Church dates from before St. Gregory the Great (P.L., XXX, 487-532." (quoted from the New Advent Encyclopedia article on Evangeliaria).