A merry heart doeth good like a medicine. So Aben Ezra, understanding the particle of comparison, which is not in the Hebrew. The ward translated "medicine" (gehah) occurs nowhere else, and probably means "healing" "relief." The clause is better rendered, a cheerful heart maketh a good healing (comp. Proverbs 15:13; Proverbs 16:25). Vulgate, aetatem floridam facit; Septuagint, εὐεκτεῖν ποιεῖ, "makes one to be in good case." A cheerful, contented disposition enables a men to resist the attacks of disease, the mind, ms every one knows, having most powerful influence over the body. Ec 30:22, "The gladness of the heart is the life of man, and the joyfulness of a man prolongeth his days." A broken spirit drieth the bones; destroys all life and vigour (comp. Proverbs 3:8; Psalms 22:15; Psalms 32:4). We all remember the distich—
"A merry heart goes all the day,
Your sad tires in a mile-a."
So the rabbis enjoin, "Give ears no room in thine heart, for care hath killed many". Religious gladness is a positive duty, and "low spirits," as Isaac Williams says, "are a sin." Asks the Greek moralist—
ἄρ ἐστὶ συγγενές τι λύπη καὶ βίος
And Lucretius (3.473) affirms—
"Nam dolor ac morbus leti fabricator uterque est."
"Workers of death are sorrow and disease."