As we thank God for His gift of St. Matthew, Apostle and Evangelist, we also praise Him for His boundless pardon and forgiveness for sinners. Patrick Henry Reardon brings this out beautifully when he discusses "The Tax Collector and His Friends" (in Christ in His Saints, p. 22-23). After he comments on the call of Levi and the call of Matthew being identical, he says:
It is much more significant, however, that all three Synoptic Gospels treat the call of the tax collector (Levi/Matthew) as a centerpiece bracketed between two stories about sinners: the paralytic being forgiven his sins and Jesus having dinner with notorious sinners. Thus set between these two events, the call of the tax collector represents above all the evangelical summons to repentance and the forgiveness of sins.
The dialogue connected with the meal at his house illustrates this meaning of the tax collector’s call. Jesus, criticized for his association with sinners on this occasion, explains that "those who are well have no need of a physician, but those who are sick" (Mark 2:17). In thus addressing sin through the metaphor of sickness, the Lord strikes again the note recently sounded by His healing the paralytic as proof of His authority to forgive the man’s sins (2:5-12).
Furthermore, summoning sinners to repentance and salvation is not just one of the things Jesus happens to do. There is a sense in which this is the defining thing that Jesus does, the very reason He came into this world. This truth is affirmed at the meal at the tax collector’s house, where He proclaims, "I did not come to call the righteous, but sinners, to repentance" (Luke 5:32; cf. Matthew 9:13; Mark 2:17). Again, it is in the context of the call of yet another tax collector, Zacchaeus, that Jesus says, "the Son of Man has come to seek and to save that which was lost" (Luke 19:10).
One of those "lost" was the Apostle Paul, who remembered himself to have been "a blasphemer, a persecutor, and an insolent man." But then he recalled that the same Lord who received the friends of the tax collector also received him: "This is a faithful saying and worthy of all acceptance, that Christ Jesus came into the world to save sinners, of whom I am chief" (1 Timothy 1:13-15).Christ can call sinners, only because He can really do something about their sins. And He can forgive their sins precisely because He has paid the price of those sins. Therefore, Jesus’ forgiveness of sins is theologically inseparable from His dying for sinners. Correct repentance, then, brings the sinner to the foot of the Cross.