A sound body keeps a sound mind.
Health is the natural condition. When sickness occurs, it is a sign that Nature has gone off course because of a physical or mental imbalance. The road to health for everyone is through moderation, harmony, and a 'sound mind in a sound body'.
The sound body is the product of the sound mind.
We need sound bodies so we can develop sound minds.
A sound soul dwells within a sound mind and a sound body.