There were ten of them in all. They were friends who were bound together by a shared tragedy: they all had leprosy---a horrible, disfiguring disease.
There's really no way to explain the horror of watching your body slowly rot away. But that was only half of the heartache.
Because it was thought that leprosy was contagious, those who suffered from it had to not only endure the ravages of disease, but also to face scorn, disgrace and loss of all dignity. They were made to live apart from the rest of society, apart from their family and friends with only fellow lepers to lean on for support and encouragement.
Lepers in Jesus' day were not only forced to live in colonies, they also had to yell out "Unclean!" whenever they approached anyone. Sometimes they were made to wear bells on their clothing to warn others of their approach...