This is the feast of St. Matthew and for his feast let me retell the story of how his Gospel came to be written. It started in the year 70 after the Romans had flattened Jerusalem and its temple. Now, their Jewish religion had always been centered on the temple, so with the temple gone, the surviving Pharisees began saying that if they were to continue as a religion they would need a new core. They decided on promoting a strict observance of kosher rules as the thing that defined Jewishness.
That presented a problem for the ten thousand Jews who had become Christians, and who were sharing meals with non-kosher Gentile Christians. The Pharisees began telling those Jewish Christians that they could not go on being both. They kept saying that by eating with sinners Jesus had broken away from Jewish traditions.
In writing his Gospel for those Jewish Christian in every page of his Gospel Matthew assured them that far from departing from Jewish tradition, Jesus had stood as the end toward which Jewish traditions all pointed.
Matthew recalled for his readers that Jesus said, “I did not come to abolish the Law and the Prophets. I came to fulfill them.” Then, in the Sermon on the Mount Matthew pointed how in one matter after another Jesus took up matters in which Moses had gone only half-way, leaving it up to Jesus to complete what God wanted of us.