We read in the Gospel, St. Matthew's own account of his conversion. The Epistle describes the famous vision where Ezechiel saw four symbolical animals, which, from the earliest centuries, have been recognized as types of the four evangelists. St. Matthew is represented by the animal with a human face, because he commences his Gospel by tracing the human descent of Jesus. His object in writing this book, which is stamped by true wisdom (Introit) was to prove that Jesus realized the prophecies relating to the deliverance of Israel and that He is therefore the Messias.
After Pentecost, the apostle preached the good news in Palestine and in Ethiopia, where he was martyred.
The name of St. Matthew is in the Canon of the Mass in the group of the apostles.
Os justi meditabitur sapientiam, et lingua ejus loquitur judicium: lex Dei ejus in corde ipsius. * Noli aemulari in malignantibus: neque zelaveris facientes iniquitatem.
The mouth of the just shall meditate wisdom, and his tongue shall speak judgment: the law of his God is in his heart. * Be not emulous of evil doers; nor envy them that work iniquity,
(Psalm 36:30-31,1 from the Introit of Mass)
Beati Apostoli et Evangelistae Matthaei, Domine, precibus adjuvemur: ut, quod possibilitas nostra non obtinet, ejus nobis intercessione donetur.
We beseech Thee, O Lord, I the prayers of blessed Matthew, Thine apostle and evangelist, assist us; that those things which by ourselves we cannot obtain, may be granted us by his intercession.
Continuation of the holy Gospel according to St. Matthew.
At that time, Jesus saw a man sitting in the customhouse, named Matthew, and He saith to him: Follow Me. And he arose up, and followed Him. And it came to pass, as He was sitting at meat in the house, behold many publicans and sinners came and sat down with Jesus and His disciples. And the Pharisees seeing it, said to His disciples: Why doth your Master eat with publicans and sinners? But Jesus hearing it, said: They that are in health need not a physician; but they that are ill. Go then, and learn what this meaneth: I will have mercy, and not sacrifice. For I am not come to call the just, but the sinners.
(St Matthew 9:9-13)
Dispersit, dedit pauperibus: justitia ejus manet in saeculum saeculi.
He scattered abroad, He gave to the poor, His justice remaineth for ever and ever.
(Antiphon at 2nd Vespers)
From the Catholic Encyclopaedia: http://www.newadvent.org/cathen/10056b.htm