At the end of the fourth Gospel, St. John's Gospel, we are told that if everything Christ did during his brief earthly life were written down, the entire world would not contain the books.
We can infer, therefore, that many - maybe even the majority - of Christ's miracles and encounters were not recorded in the New Testament.
So why did St. Luke include this one? Clearly because of the lesson that Christ teaches us by it: the beauty of gratitude. The one leper who came back to thank Jesus is praised for this gratitude. We can almost hear the sadness in Christ's heart at the lack of gratitude in the other nine who were healed.
Why does Christ value gratitude so much? Is he vain? Is his self-esteem so weak that he gets depressed if we don't praise and thank him? No. He values gratitude because gratitude is valuable - it's valuable for us, for the health of our souls.
In the first place, gratitude keeps us grounded in the truth, which is key for our ongoing relationship with God. To be ungrateful to God is not only unjust, but it's also living an illusion. The simple fact is that everything we have is a gift from God: creation, life, talents, opportunities, hope in heaven, the grace that helps us persevere in doing what is right - these are all God's gifts. We don't create ourselves!
In the second place, gratitude is the perfect antidote to sin. Sin turns us in on ourselves, like an ingrown toenail; gratitude opens us up to God and neighbor.
It directly contradicts self-centeredness, self-indulgence, and self-absorption. It builds bridges, unites communities, and softens hearts. It counteracts depression and releases anxiety.
Gratitude is one of the most beautiful flowers in the garden of virtue - what a pity that it's so rare!
Physical and Moral Leprosy
Christ's encounter with these lepers is so powerful partly because leprosy itself was so terrible. Leprosy was and still is an incurable and deadly disease. Leprosy is a bacterial infection that causes the extremities of the body - fingers and toes, hands and feet, nose, ears, and mouth - to die and slowly rot away, even while the person remains alive.
It was so contagious that even the lepers' closest relatives did not dare to come near them. In ancient times, lepers were required to live in isolated colonies.
If they had to travel, the law required them to ring a bell wherever they went, shouting out, "Unclean! Unclean!" This explains why these ten lepers addressed Christ "from a distance", as St Luke points out.
On top of the isolation, lepers had to live with the almost unbearable pain and stench of their own decaying bodies. Leprosy was a long, humiliating, and dismal agony, the most horrible of ancient diseases.
Jesus frees these ten lepers entirely from their agony, giving them a brand-new life. And yet, only one of them takes the trouble to thank him for it - and that one happens to be a Samaritan, the one least likely to respect a Jewish rabbi.
We are all moral lepers. The whole human race was infected with mortal selfishness by original sin, a selfishness that rots our souls and societies just as leprosy rots the body.
Christ saved us. He opened the floodgates of God's grace through his incarnation, passion, and resurrection. And then he gave us constant access to that grace through the Church, the sacraments, and his many other gifts.
We all recognize what Christ has done for us - that's why we are here today. Christ's message today is that he wants our recognition to go deeper, to become an attitude of gratitude.
The First Four Commandments
God wants us to develop the virtue of gratitude because he wants us to experience the joy that comes from knowing we are loved by him without limits or conditions. It is such an important virtue, that God built it into four of the Ten Commandments - the first four, in fact.
The First Commandment enjoins us to love and worship the one true God and none other. Worship starts by recognizing God's greatness, praising him for it, and thanking him for his benefits. The heart of worship is gratitude.
This is why Naaman the Syrian, whom we heard about in the First Reading, changed his religion after being cured. He wanted to give the prophet Elisha a gift, to show his gratitude to Israel's God. But Elisha wouldn't accept it.
So instead, Naaman loads up two mules with sacks full of soil taken from around the Jordan River.Naaman wanted to build an altar back home on top of some land that was connected to the God of Israel, and worship there. He says, "I will no longer offer... sacrifice to any other god except the Lord."
He was fulfilling the First Commandment, because he was grateful to God. The Second and Third Commandments help specify the first one: they enjoin us to keep God's name holy, and to keep the Lord's Day holy too. These are other ways to show and grow our gratitude to God, acknowledging that he is the source of all good things.
The Fourth Commandment enjoins us to always be grateful to our parents, through whom God has given us so many gifts: life, education, faith...
Truly, the virtue of gratitude is at the very core of our spiritual lives.
Today, as Jesus renews his gifts to us in the Holy Eucharist, let's promise him that this week we will unclog the pipeline of gratitude, so that we can be filled with lasting joy.