Note, 1. It is healthful to be cheerful. The Lord is for the body, and
has provided for it, not only meat, but medicine, and has here told us
that the best medicine is a merry heart, not a heart addicted to vain,
carnal, sensual mirth; Solomon himself said of that mirth, It is not
medicine, but madness; it is not food, but poison; what doth it? But he
means a heart rejoicing in God, and serving him with gladness, and then
taking the comfort of outward enjoyments and particularly that of
pleasant conversation. It is a great mercy that God gives us leave to
be cheerful and cause to be cheerful, especially if by his grace he
gives us hearts to be cheerful. This does good to a medicine (so some
read it); it will make physic more efficient. Or it does good as a
medicine to the body, making it easy and fit for business. But, if
mirth be a medicine (understand it of diversion and recreation), it
must be used sparingly, only when there is occasion, not turned into
food, and it must be used medicinally, sub regimine--as a prescribed
regimen, and by rule. 2. The sorrows of the mind often contribute very
much to the sickliness of the body: A broken spirit, sunk by the burden
of afflictions, and especially a conscience wounded with the sense of
guilt and fear of wrath, dries the bones, wastes the radical moisture,
exhausts the very marrow, and makes the body a mere skeleton. We should
therefore watch and pray against all melancholy dispositions, for they
lead us into trouble as well as into temptation.