死的缘故。the phrase sound doctrine, in which sound is hygiainos, “health-giving.”英文中“卫生的”Hygeia, ancient Greek goddess of health (from Latin Hygea, from Greek Hygieia, from hygieia health, from hygiēs sound, healthy)就是从这个译作“纯正的”和“健全的”hygiainos来的，这也是为什么sound doctrine是让人成圣的真理，而珍珠则是污秽的言语。这也是为什么“污秽的言语”有些英文版本译作unwholesome（不卫生的）word的缘故