Leprosy is a mildly contagious, progressive skin disease that until recently could not be treated and as such would lead to permanent damage of skin, nerves, eyes, and appendages.
In biblical times, because of a lack of treatment and its infectious nature, the Jewish law contained strict guidelines for how leprosy and lepers would be handled. People with leprosy were segregated from the general population and were required to call out “unclean” when other people approached them.
It is noteworthy that Jesus healed many lepers, as did the prophet Elisha (2 Kings 5).
There is a story of Jesus dealing with 10 lepers (leprosy is an infectious skin decease that eats away the flesh). Keeping their distance, as was the practice of the day, they call out to Jesus for help.
Jesus tells them to go present themselves to the priest. (It was also the practice that a leper who became better, needed to go to a priest for confirmation before re-entering society.) The lepers comply; as they do, they are “cleansed” of their leprosy.
One man, seeing what happened, returns to Jesus, thanking him.
Jesus commends the man for doing so, but is surprised that only one person returned to give thanks. Then the man was made “well.” (Other translations say he was “healed,” restored,” or “made whole.”)
There seems to be a distinction between being “cleansed” and being made “well.” One thought is that being cleansed meant that the leprosy was gone, but its ravages remained, whereas being made “well,” restored the flesh to its pre-leprous condition. Another thought is that being made “well,” addressed the whole person, encompassing the psychological and emotional aspect of having been ostracized and devalued as a person.
Whatever the precise meaning, it is clear that the man who thanked Jesus — and didn’t take his generosity for granted — was given even more as a result.