Dictionaries define "wellness" as a quality or a state of being healthy in mind and body.
With this kind of definition, we begin to deny the state of health of a soul which in turn brings sickness to the body and the mind. For without God, we cannot afford to remain healthy.
Leprosy is a sure state of being sick. But in it also contains the sickness of the spirit and the sickness of the community that ostracizes the sick. A person who is sick with leprosy suffers the loss of his friends. Worse, he is separated from the society itself. When we sin, we suffer the loss of a community.
Leprosy is marked by the death of the senses. Through sin, we also lose the sense of the Divine; we become callous to God.
Let us learn from Jesus. When he heals, he heals the whole person; that is why "wholeness" is a lot better. We see the entire state of health of the person, bodily, mentally, and spiritually. And we cannot deny Jesus of the opportunity to heal us.
Jesus cures the social and individual leprosy. His touch connects the person back to the fold. The person who repents is embraced by the whole community.
Jesus wants us to be healed. Moses' procedure for the leper is only palliative and superficial. It doesn't really solve the problem. Tell me if our solutions are merely palliative and not wholistic.
Third, Jesus brings our sensitivities back, especially our sensitivity to God and one another. We can finally feel one another, and in feeling, help one another. Jesus unites us more than we can unite ourselves.