John Gills Exposition of the Bible Commentary - Proverbs 17:22
A merry heart doth good like a medicine ,.... Does the body good, makes it healthful and vigorous. Cheerfulness of spirit has a great influence upon the body, and much contributes to the health and welfare of it; see Ecclesiastes 9:7 ; and especially a heart full of spiritual joy, peace of conscience, flowing from the blood of Christ, joy in the Holy Ghost, a rejoicing in Christ Jesus and his righteousness, and in hope of the glory of God, much affect even the outward man. Or, "a merry... read more
Matthew Henry's Complete Commentary - Proverbs 17:22
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... read more