The rabbis were impressed with the profoundly important role that emotions play in life. The heart, which they looked upon as the seat of emotion, was regarded by them the principal source of control over all human actions. "All of man's bodily organs are dependent on the heart," was a Talmudic dictum. It is the heart therefore which may be said to carry responsibility for whatever we do in life. Thus one rabbinic comment offers us the sweeping generalization: "The heart sees, hears, speaks, walks, falls, stands, rejoices, hardens, softens, grieves, fears, is broken, is haughty … persuades, errs, fears, loves, hates, envies, searches, reflects. …"
The rabbis prized highly the ability of some people to control their emotions. To control one's emotions and to bring life under the directing voice of reason was regarded by the rabbis as the mark of true heroism. "Who is a hero?" one rabbi asked in the ethical treatise Abot. His reply was: "He who controls his passion."