Matthew the Apostle and Evangelist, also called Levi, was sitting at his tax-collector's desk in Capharnaum when he was called by Christ. He followed Him at once, and also gave a feast for Him and the other disciples. After the resurrection of Christ, while Matthew was still in Judea before going to the district which it had fallen to his lot to evangelize, he wrote the Gospel of Jesus Christ in Hebrew for the sake of the Jews who had become believers. Then he went to Ethiopia and preached the Gospel, confirming his teaching with many miracles.
By one of his greatest miracles, that of bringing back to life the king's daughter, he converted the king and his wife together with the whole country to the faith of Christ. When the king died, his successor Hirtacus wished to marry Iphigenia, the daughter of the former king; but she had vowed her virginity to God, and she persevered in her holy determination. Since the vow had been taken through Matthew's influence, Hirtacus had Matthew killed at the altar while celebrating Mass.
It was on the 21st of September that Matthew's apostolic work was crowned with the glory of martyrdom. His body was taken to Salerno, and later, under Pope Gregory VII, it was transferred to the church dedicated to St. Matthew. There it is honored devoutly by a great number of persons.
Taken from The Hours of the Divine Office in English and Latin, Vol. III: August to Advent (Collegeville, Minnesota: Liturgical Press, 1963), pp. 1566-1567.